Mike Stanley was C.J. Nitkowsk’s biggest nemesis. In seven career plate appearances versus the now-Atlanta Braves broadcaster, Stanley homered twice, hammered a double, and walked four times. That added up to a 4.333 OPS. Of the 592 batters Nitkowski faced over 10 big-league seasons, no one was more injurious to his stat sheet.

Somewhat surprisingly, the pair of gophers — one at Tiger Stadium in 1996, the other at Fenway Park in 2000 — aren’t what the southpaw most remembers about his matchups with the slugging catcher/first baseman. What stands out is the two-bagger.

“I have a story about Mike Stanley,” explained Nitkowski, who made 336 MLB appearances, 213 of them with Detroit, while pitching for eight teams from 1995-2005. “As a kid who grew up in New York and was a Yankees fan, I always knew who he was. He was a Yankee when I was in high school. When I got drafted and went down to Orlando for my first spring training [with the Cincinnati Reds in 1995] — I went early to get out of the cold — I was working out with Chad Mottola, who is now the hitting coach for the Rays. He was my first roommate in professional baseball.

“Chad lived down there,” continued Nitkowski. “Mike Stanley happened to live in the same neighborhood, and they worked out together once in awhile, so I met him. I was 21 or 22 years old, so it was a big deal. You meet a big-leaguer and are trying to play it cool — you’re a professional now — but it was Mike Stanley. That’s cool. I thought it was kind of a big deal. I got to know him a little bit.”

Fast forward to August 12, 2000. Stanley was playing for the Oakland Athletics, while Nitkowski was pitching in relief for the Tigers. A request was made in the dugout during the sixth inning. Read the rest of this entry »

A long time ago, Keibert Ruiz was one of the top catching prospects in baseball. He was so highly regarded that he was a significant piece of the Nationals’ return in the Max Scherzer and Trea Turner trade with the Dodgers in 2021. After a solid first full season in Washington the following year, he signed an eight-year extension worth $50 million in March 2023. Unfortunately, that’s when the bottom fell out. Over the last three years, Ruiz has been the worst qualified position player in baseball, “accumulating” -1.9 WAR.

When the Nationals acquired Harry Ford in a trade with the Mariners this offseason, it was fair to wonder if Ruiz’s days as the team’s primary backstop were numbered. He had been a disaster both at the plate and behind it. His 79 wRC+ over the last three years was a hair higher than Patrick Bailey’s 76 mark, but instead of offsetting that offensive futility with elite defense, Ruiz was the worst defensive catcher in baseball. It’s shocking, then, to see that he has so completely turned things around this year; he’s already accrued 0.8 WAR and has been the 11th-most valuable catcher in baseball in just 34 games.

Let’s tackle the most surprising development first: All of a sudden, Ruiz is providing positive value behind the plate. Among the 53 catchers who caught at least 1,000 innings over the last three years, Ruiz was the second-worst framer, the second worst at throwing out base stealers, and the sixth-worst blocker. This year, he’s added two runs via framing and has been a slightly above-average blocker. His throwing hasn’t improved all that much according to Statcast, but he also hasn’t been challenged very often, so that area of defense hasn’t really affected his overall defensive value.

Last year, Ruiz suffered two concussions within a few weeks of each other. The first came on June 23, when an errant foul ball hit him in the head while he was sitting in the dugout. The second came just a week and a half later — and just two days after he had been activated off the 7-day concussion IL — when a foul tip struck him in the mask. He attempted to return to play in September, but he was shut down from his rehab assignment after his concussion symptoms returned. In an effort to reduce his risk behind the plate, the Nationals had Ruiz adjust his stance so that he’s now crouching lower to the ground:

In the picture above, you can see that at the pitcher’s release, Ruiz’s back isn’t as upright and his head is a little lower to the ground. The team thought that a lower stance would allow more foul tips to fly over his head instead of into his mask. That might have been the intended goal of the new position, but the effect on Ruiz’s ability to receive pitches has transformed his defensive metrics. If we look at Statcast’s detailed framing data, over the last three years, Ruiz had really struggled to receive both low pitches and pitches to his right:

It’s reasonable to think that sitting lower in his stance has helped him to frame those low pitches much more effectively. What’s even more surprising is that the right-hand side of the plate is now his strongest framing zone. In addition to benefiting his receiving, a lower crouch has probably helped him block errant pitches that he might not have been able to get to previously.

Going from being one of the worst defensive catchers in baseball to an above-average one is a tremendous improvement on its own, but Ruiz has also taken a step forward as a hitter. Ruiz got off to a familiar slow start at the plate this year; though May 6, he was running a .182/.203/.303 slash line, with a hugely disappointing 37 wRC+. As Spencer Nusbaum of The Athletic reported on Thursday, Ruiz met with the Nationals coaching staff on May 7 to build a plan for improvement. That same day, he smacked a pair of doubles and a home run. Over his last 11 games, he’s collected 16 hits, seven doubles, and three home runs, raising his season line to .262/.277/.486 (109 wRC+). The plan seems to have worked.

Two things keyed this offensive outburst. First, Ruiz is being more selective when it comes to which pitches to swing at, and second, he’s swinging to do damage when he gets a good pitch to hit. Here’s how manager Blake Butera put it in an interview with Jessica Camerato of MLB.com:

“That’s the one thing with Keibert is, he can cover a lot of pitches but he can also hit the ball really hard. And it’s really hard to hit pitches hard when you’re swinging at everything and just making contact. So one thing we put on him was, shrink the zone a little bit, trust your hand-eye coordination, even if that means taking some borderline pitches that are strikes. Wait until you get a good pitch to hit. Then he’s doing the work from there.”

Throughout his career, Ruiz has displayed excellent bat-to-ball skills and a fantastic ability to cover the entire plate; it’s the reason his career strikeout rate is just 11.1%. But his aggressiveness and propensity to put the ball in play is also why his career walk rate is just 4.7%. With a new selective approach in mind, Ruiz has cut his overall swing rate to 47.5%, a five point drop from where it’s been in the recent past. He’s given up nearly all of those swings on pitches located in the zone; his chase rate is essentially unchanged, but his zone swing rate is down nearly 10 points.

Despite that increased selectivity, he’s still making contact just as often, only now that contact has a little more oomph behind it. Ruiz has significantly improved his contact quality, and most of the improvement has come as a right-handed hitter. Throughout his career, he’s run a neutral platoon split as a switch-hitter, but his underlying batted ball metrics were significantly worse from the right side despite the results indicating otherwise:

This year, Ruiz is doing a ton more damage against left-handed pitching. He’s increased his bat speed from the right side by more than two ticks and has seen huge improvements in every meaningful batted ball metric. He’s also seen a jump in batted ball quality from the left side, albeit a smaller one. That growth appears to stem from his intent at the plate. He’s seeking good pitches to hit and is looking to drive them in the air to the pull side. His pull rate is all the way up to 67.4%, the largest increase of any batter this year, and he’s elevating his contact a lot more often as well. The results over the last few weeks speak for themselves.

For now, Ruiz is still splitting time behind the plate with Drew Millas. He has started a little over half of the Nationals’ games this season and just 11 of the 20 games since the fateful meeting that set him on this course. Millas was a well-regarded catching prospect in his own right not too long ago, but he hasn’t exactly impressed during parts of four seasons in the big leagues. He’s currently running a 41 wRC+ with adequate defense behind the plate. And Ford isn’t knocking on the door of the big leagues, either; the young catcher has mustered just a 74 wRC+ in Triple-A this year. If Ruiz continues bashing the ball and is able to keep up the good work defensively, it wouldn’t be surprising to see him reclaim his role as the team’s everyday catcher in short order.

With their plan for improvement in place, the Nationals have to be thrilled to see such positive results so quickly from Ruiz. I’m sure there will be bumps in the future — we’re talking about just 43 plate appearances since he made these changes to his approach — but with the support of the coaching staff, Ruiz appears to have been set on a path to success.

Spencer Strider had a fascinating first inning at Fenway Park on Tuesday. The Atlanta Braves right-hander threw 10 pitches in the frame, and it took him just five to retire the final three batters he faced. The first two batters were another story entirely. Jarren Duran walloped the second of Strider’s offerings over the right field fence, and Ceddanne Rafaela followed by depositing his fifth bullet over the Green Monster. The Red Sox led 2-0 before he had recorded an out.

What was that inning like for Strider? Wanting to find out, I approached him the next day to see if he’d be amenable to a pitch-by-pitch revisiting of what had happened. We’d had such a conversation back in his rookie season, albeit under far different circumstances: He’d fanned the side on 11 pitches in his lone inning of work.

Strider was happy to oblige, so I began by asking him if his game plan differed from 11 days prior, when he’d started against the Red Sox in Atlanta.

“There was some variation,” the righty replied. “I walked Duran to lead off the game in the previous outing, and I felt like some of that was a game-plan thing where we wanted to go with the heater; the walk was a lot of arm-side heaters. For my stuff, and kind of my mechanics, we wanted to target the glove side and get ahead [on Tuesday]. And I did, although I kind of pulled it down a little bit more than we were trying to do. Then we went back to it, as was the plan, and I kind of threw it in the same spot. The down-and-in heater to lefties isn’t a spot where you want to go, especially when they’re sitting heater. Maybe he pops it up or grounds out. Maybe he takes it again. Instead, he hit a homer. Big league hitters do that.”

The three pitches he threw to Rafaela were all elevated. Read the rest of this entry »

When I announced my intention to write about Antonio Senzatela, Jon Becker burst into my Slack DMs like the Kool-Aid Man to demand I use a Penn and Teller-based headline. Credit where due: It was a great idea.

You know what’s not traditionally a good idea? Writing about Antonio Senzatela.

The rigorous study of baseball empirics has made us all smarter and better, but there are a few things I miss about the old days. Foremost among them is Nichols’ Law of Catcher Defense, an old pre-sabermetrics axiom which states the following: A catcher’s defensive reputation is inversely proportional to his offensive abilities. Read the rest of this entry »

Hello. While on paternity leave, I kept a journal about baseball and my daughter, who is not named Derek Jr., but who will henceforth be referred to as Derek Jr. This is the second installment of that series. You can read all of the entries here.

April 17

Like any new parents, my wife and I spend a lot of time staring at our baby and talking about how beautiful she is. Of course we do. Evolution has programmed us to be completely overwhelmed by the baby’s beauty so that we don’t leave her on the doorstep of the nearest convent when we get fed up with the wailing and the sleepless nights and the relentless, unceasing, never-ending pooping. It has worked. We are ensorcelled. Derek Jr.’s future is wimple-free. But I’m starting to think it has hit my wife harder.

I say this because she has started to insist that Derek Jr. is “an objectively beautiful baby.” Objectively beautiful. You’re familiar with beauty, right? The thing that is, famously, in the eye of the beholder? Apparently one beholder knows better. It’s not enough that she thinks the baby is beautiful, and that everyone tells her all day long how beautiful the baby is. She now needs it to be proven empirically.

I used the word “insist” earlier because I have been pushing back ever so slightly on this one. I spend a whole lot of time analyzing players or trends, and it requires rooting out biases and confounding variables. Call me crazy, but I’m picking up on a possible conflict of interest here. I’m not prepared to get in a fight over this, but I have gently pointed out that the fact that my wife is throwing around the word “objectively” here is — objectively — hilarious. Read the rest of this entry »

After posting an excellent 125 wRC+ over his first two seasons, James Wood is establishing himself as one of the best hitters in baseball this year. The 23-year-old National is running a 169 wRC+, third best among qualified batters, and he’s on pace for 43 homers, 26 stolen bases, and 7.2 WAR. Everybody knows the parameters of Wood’s game by now. He’s 6-foot-6, extremely choosy at the plate, and so spectacularly powerful that his proclivity for whiffs and groundballs barely holds him back. This year, he’s improved on both fronts, dropping nearly 10 percentage points from his groundball rate and adding nearly four points to his contact rate on pitches in the strike zone. It’s huge news – James Wood-huge even – and if he can hold on to even some of those gains, he’s going to live at the top of the leaderboards for a long, long time. Today, however, we’re going to talk about a leaderboard where Wood ranks dead last.

If you head over to Baseball Savant’s new ABS challenge leaderboard, you’ll find Wood all the way at the bottom. A big caveat before we get going: The challenge system is very new, and because each player challenges so few times, the sample sizes are very small. Moreover, everyone involved is still adjusting to the system, so the trends we’re seeing now are likely to change. In this article, I’m going to be overreacting to these early numbers. It’s way too soon for big proclamations. However, I don’t think it’s too soon to look for patterns and draw some early conclusions about players who stand out as starkly as Wood does. End of caveat.

Now let’s go to the leaderboard and sort by either Net Overturns or Net Runs. There’s Wood, dead last. According to Statcast’s reckoning, an average batter who saw the same pitches Wood has seen would have made 4.8 more successful challenges and netted their team 1.4 more runs. No player has been worse, and even if you ignore the advanced numbers for a moment, Wood’s record tells you all you need to know. He’s made 13 challenges. He’s won three of them and lost 10. For those of you keeping score at home, that stinks. The average batter has won 47% of their challenges, twice as many as Wood. Read the rest of this entry »

Last Friday, after missing the entire 2025 season due to Tommy John surgery, Gerrit Cole fared well in his return to the Yankees rotation, firing six scoreless innings against the Rays even while struggling to miss bats. On Wednesday night in Kansas City, Cole truly looked back, this time throwing 6 2/3 scoreless innings while striking out 10 Royals without issuing a walk. The former Cy Young winner’s reassuring performance is a welcome development for a rotation that has weathered some high-profile absences — and will have to continue doing so.

The Yankees began the season with Cole, Carlos Rodón, and Clarke Schmidt all recovering from elbow surgeries, and while the first two have now returned, Max Fried — their most valuable pitcher last season — has been sidelined for a spell, as has 2024 AL Rookie of the Year Luis Gil. Nonetheless, the team’s rotation has been one the game’s best thus far, leading the majors in WAR (7.5), leading the AL in FIP (3.22), and ranking a close second in the league in both ERA (2.98) and strikeout rate (24.5%). Despite backing that unit with the most potent offense in the league, the 34-22 club finds itself trailing the Rays (34-19) by 1 1/2 games in the AL East.

Prior to last Friday, Cole’s last competitive appearance in the majors had been a reminder of a golden opportunity lost: His inexplicable failure to cover first base in the fifth inning of Game 5 of the 2024 World Series fueled the Dodgers’ comeback from a 5-0 deficit on a night they ended up clinching the title. Limited to 17 starts that season due to nerve irritation and edema in his elbow after finally bringing home a Cy Young award in 2023, Cole made just two appearances in spring training last year before being diagnosed with a torn UCL and undergoing surgery. He progressed enough in his recovery to make two brief appearances in Grapefruit League games this spring, then continued his rehab by making six starts spread across three minor league levels before returning to the Yankees. Read the rest of this entry »

Joe Ryan is about as steady a pitcher as you’ll find in the big leagues. Since his first full season in the majors, 2022, Ryan has never made fewer than 23 starts. He’s never thrown fewer than 135 innings nor more than 171, and his season-by-season WAR has stayed between 2.2 and 3.1. He hasn’t been a front-end starter, but he’s making just $6.2 million, which is a tremendous bargain. He was a hot commodity who somehow stayed put during the Twins’ fire sale last summer; if Minnesota is out of contention again, you’ll probably hear his name come up at this coming deadline, as well.

It also helps that Ryan is having a career year at the right time. He’s already at 2.1 WAR on the season, and we’re only about a third of the way through the calendar. That puts him fifth in the league. He’s also sixth in FIP, 12th in strikeouts, and 10th among qualified starters in K-BB%. Read the rest of this entry »

As the caretaker of the ZiPS projection system, I answer a lot of questions about both how it functions and the numbers that it spits out. One question I get a lot is why the system has consistently underrated the Milwaukee Brewers, which it has over the last five seasons and by a significant margin. While I’ve talked a little bit about this issue, mostly in offhand remarks in chats and on social media, addressing that question in detail is probably necessary at this point. Of course, ZiPS isn’t alone in underrating the Brewers. But as the system’s sole developer for nearly a quarter of a century, I have a responsibility to both be as transparent as possible and improve the model as much as I can.

So, how has ZiPS done with the Brewers historically? Well it turns out that since the system was first developed, worse than it has with any other major league franchise! Here are the results for ZiPS vs. Reality since 2005. I’ll note the columns don’t precisely add up, as ZiPS projects full 162-game seasons (or a 60-game one in the case of 2020) and there are a bunch of times that teams played 161 or 163 games:

One source of error that’s really difficult to control for is what a team does at the trade deadline. Many of the teams that have overperformed their preseason projections have added talent during the season; conversely, underperformers have a tendency to trade talent away. That’s challenging to model, since it involves trying to project players who aren’t currently in the organization as part of the team, even though we have little idea who those players will actually be four months in advance. I actually created a model based on team quality, age, payroll, recent record, and trade history to get an idea of the likelihood a team will be a buyer or seller in an upcoming season. But while it sort of works, its accuracy isn’t up to the level where I’d include it as part of a projection.

Historically, the Dodgers and Yankees have been two of the league’s most aggressive buyers, so it isn’t surprising to see them atop the list of the biggest ZiPS misses. But while the Brewers have made some big in-season moves — the biggest arguably being the CC Sabathia trade in 2008, which was one of the most effective trades of this type ever — they aren’t on the buy side as frequently as some of the other underprojected teams. So, what’s going on here?

First, here’s an overview of how the percentiles for team projections have worked out. Ideally, you want 10% of teams to exceed their 90th-percentile projection, 20% of teams to exceed their 80th, and so on:

ZiPS does a pretty good job in the aggregate. To put it simply, the basic job of a projection system is to know the range of possible outcomes, and be wrong by the appropriate margins the proper number of times. It would be easy to say “Hey, projections work as they’re supposed to in the aggregate, and some team is inevitably going to have the worst projections of the 30, so whatever,” but that doesn’t mean that we shouldn’t investigate these issues and assess whether there’s something systemic that the model is missing. Especially so in a case like Milwaukee, where nearly two-thirds of the 21-year error comes from the last five seasons (417 projected wins vs. 463 actual wins).

The ZiPS projected standings have two components: the projections themselves and the estimates of who actually ends up with playing time. To get an idea of how much of the ZiPS misses are errors in projection compared to errors in playing time, I will frequently re-project team wins using the actual playing time for each player after the season is done. Re-projecting the 2021-2025 Brewers using their preseason projections but the players’ actual playing time makes the issue a lot clearer:

Knowing each player’s actual playing time doesn’t eliminate the errors, but it whittles the missing 46 wins all the way down to 12. In other words, ZiPS isn’t doing a bad job with the projections; Dan Szymborski has done a poor job guessing which players will end up with playing time for the Brewers! Injuries are sometimes a reason for playing time discrepancies, but they typically result in teams underperforming their projections as regulars miss time. Not only have the Brewers overperformed, they’ve done so while not being particularly good at avoiding injuries; they’ve actually lost slightly more wins than the average team due to IL stints over the last five years.

Instead, what appears to be happening is that the Brewers have been extraordinarily successful at giving more playing time to players exceeding their projections. For example, there were 62 hitters who had seasons with at least 200 plate appearances for the Brewers from 2021 to 2025. As a group, ZiPS only underestimated them by 1.5 points of wRC+ in the aggregate (104.7 actual vs. 103.2 projected). But of the 33 hitters who exceeded their projected wRC+, 28 of them received more plate appearances than I had as my baseline expectation. The same is true for pitchers, especially relievers. Now, there’s a natural tendency for teams to give more playing time to players who are outperforming their projections and less to guys who are underperforming, but the Brewers have been notably more successful at this than the rest of the league. From 2021 to 2025, 81% of their qualifying players who outperformed their expected wRC+ or ERA+ got more playing time than I expected as a baseline. To put that into context, the league-wide rate was just under 61%, and no other team was above 70%.

So, how do I fix the Brewers’ projections? That’s a bit of a craggy problem that I’m still working on. This offseason, I tried to be more aggressive in my assumptions about who would get playing time for Milwaukee based on the quality of their projections. As a result, ZiPS forecast the team for 85 wins. Naturally, the Brewers are on pace for 99.7 wins as of Wednesday morning. I may need to more accurately project actual front offices; if the Brewers are simply better than everyone else at evaluating their talent with information only they have access to, it’s not something I can directly correct for. Unless, of course, the Brewers decide to just give me all their internal data, which seems unlikely. Or if I, say, catch Dan Turkenkopf in a giant net and imprison him in my tool shed until he spills the beans. As much as I like improving projections, I don’t think my employer would appreciate if I did so by committing federal crimes, so I’ll simply have to keep trying. Being wrong is how we improve predictive models, and let’s just say that the Milwaukee Brewers continue to give me a lot of opportunities to learn.

When he broke in with the Brewers last season, Jacob Misiorowski was tough to miss, unless you were a hitter trying to catch up to his ridiculous velocity. The gangly 6-foot-7 righty announced his presence by reaching 100.5 mph on his first major league pitch and topping out at 102.2 mph in five no-hit innings against the Cardinals in Milwaukee on June 12. He followed that up with six perfect innings against the Twins before yielding a walk and a homer, and was named to the National League All-Star team as an injury replacement after just five starts. He soon leveled off, and finished with comparatively unspectacular numbers — he was an afterthought in the NL Rookie of the Year voting — but this season is a different story. The 24-year-old righty has dominated hitters like a true ace, and has improved in practically every important statistical category.

Misiorowski’s latest outing, once again facing the Cardinals in Milwaukee, was both a gem and an awe-inspiring display of firepower. Monday’s effort began with an unprecedented, if somewhat unproductive, barrage of six consecutive four-seam fastballs to JJ Wetherholt, each clocked at 103.0 mph or higher — but four of them were well outside the strike zone, resulting in a walk:

Misiorowsi overcame the leadoff walk, escaping the inning by throwing just seven more pitches on back-to-back three-pitch strikeouts of Iván Herrera and Alec Burleson, then a first-pitch groundout by Jordan Walker. In fact, he retired 15 straight hitters after the walk, again completing five no-hit innings before yielding a leadoff single to Pedro Pagés in the sixth. The Cardinals turned that into a run after speedster Victor Scott II replaced Pagés on a forceout, took third on a single to right field by Wetherholt, and scored on a grounder by Herrera, but Misiorowski stuck around to complete the sixth and seventh innings before departing with a 4-1 lead. The Brewers won, 5-1. Read the rest of this entry »