At first, it was a trickle. A Gregory Soto here, a Hoby Milner there. On Tuesday, though, we were staring down a veritable deluge. In a single day, the low-to-mid-tier short-term left-handed pitching market got ransacked like a Ralph’s on the Wednesday before Thanksgiving. In rapid succession, three cromulent southpaws inked deals. First, it was Caleb Thielbar, returning to the Cubs on a one-year pact. Foster Griffin followed, lured back from Japan by a $5.5 million guarantee from the Nationals. Finally, Caleb Ferguson linked up with the Reds, also for a single year. (Later on Tuesday, Drew Pomeranz joined the party; he agreed to a one-year contract with the Angels, which be covered in a separate post.) Let’s assess each of these deals in the order in which they signed:

Caleb Thielbar

When Thielbar appeared on one of these roundups around this time last year, it was under sorrier circumstances. The weathered middle reliever had just dropped a stinker, walking 11.1% of hitters on his way to 47 1/3 innings of a 5.32 ERA. The Cubs handed him a “here’s your last chance” $2.75 million; given that Thielbar was heading into his age-38 season, another shoddy campaign would’ve likely marked the end of a surprisingly successful career for the former 18th rounder.

Instead, the wily veteran innovated his way out of a hole, adding a new pitch and delivering a vintage Thielbar performance. The terms of his deal have not yet been disclosed, but considering that many relievers this offseason have signed for more money than they were expected to get, Thielbar almost certainly received a healthy raise to keep playing ball for a living.

In 2025, his strikeout rate remained down a few points from his 30ish% peak, but Thielbar got his command back, in part due to his decision to replace a good chunk of his big old sweepers with a tighter, cutterish hard slider. The slutter (sorry) was a genius bridge between his three other pitches, which are all relatively easy to identify out-of-hand. By adding a pitch that he could conceivably tunnel with his four-seamer, curveball, and sweeper, he seems to have increased the effectiveness of his entire arsenal.

See all of those yellow dots on the pitch plot above? That pitch did not exist before this year. In 2024, Thielbar primarily attacked lefties with the sweeper, throwing it 55% of the time in same-handed matchups. A pitch with all that movement — 14 inches of horizontal movement on average — is hard to land for strikes. His new slider doesn’t have that sort of crazy break, and he had a much easier time throwing it in and around the zone.

And it wasn’t just a chase pitch to lefties. Thielbar also used the new slider as a soft-contact generator against right-handed batters, jamming them inside with respectable velo and glove-side break:

Otherwise, it was vintage Thielbar, slinging slow, high-ride fastballs and some of the prettiest curveballs in the sport. He handled righties and lefties alike, and will assume a similar role in the Chicago bullpen, navigating medium-high leverage situations, particularly when that leverage context coincides with a run of lefties.

Foster Griffin

Last we saw of Griffin stateside, it was 2022, and he was languishing in Quad-A limbo, making brief cameos with the Royals and Blue Jays before hopping on a bus back to Omaha or Buffalo. Back then, he was a fringy bullpen arm, leaning on a cutter with a movement profile that coincidentally resembled Thielbar’s new slider. On top of the cutter, Griffin featured a dead-zone four-seamer at 93 mph, a pretty standard curveball, and a changeup with some quality arm-side fade.

The uninspiring stuff and varied arsenal felt more befitting of a backend starter, and starting is exactly what Griffin took to with the Yomiuri Giants, where he pitched some excellent ball for three seasons. The final was his finest for the Tokyo-based club. He posted the third-best FIP (1.78) among NPB hurlers with at least 70 innings pitched, striking out a quarter of hitters and allowing just a single home run.

What changed? For that, I’ll hand it over to James Fegan, who wrote up a little blurb on Griffin for The Board:

The addition of a low-80s splitter is the profile-changing development since the last of Griffin’s eight career big league innings. Its raw action won’t knock you out of your chair, but it flirted with a 50% miss rate this past season because Griffin almost never leaves it in mistake locations. His steep approach angle makes the pitch nearly impossible to lift, allowing Griffin to allow fewer home runs (18) in over 300 innings in Japan than he gave up in his last full season in the PCL (20) in 2019. Even topping out at 93 mph now, this is still too much of a nibbling profile to project him beyond a multi-inning swingman role. But now that he can wield his splitter as an out pitch to either side, it’s easier to see Griffin carving out a Tyler Alexander-shaped niche at the end of a pitching staff.

The prospect team gave Griffin a 35+ FV grade, suggesting he is unlikely to do much more than hoover up innings for the Nationals. But if there’s a club in need of some innings-hoovering, it’s the Nats, who have a bunch of question marks on the staff after MacKenzie Gore, and that’s assuming they hang onto Gore, which, who knows.

Caleb Ferguson

The second left-handed Caleb in this roundup is 10 years younger than his predecessor. Once a whiff chaser with shaky command, Ferguson leaned hard into contact suppression in 2025, scaling back his four-seamer against same-handed hitters while boosting the sinker to nearly 50% usage. At times, this worked great. His strikeout rate dropped over eight percentage points, but the heavy combination of sinkers and cutters gave Ferguson some of the lowest barrel rates and exit velocities in the league.

Chasing weak contact as a relief pitcher can be a blessing and a curse. Attacking the zone with three fastballs keeps the walks down and the extra base hits to a minimum. But it also means a big chunk of balls in play, and one day the BABIP gods will rise with vengeance and rain misery upon your poor ERA. Unfortunately, this happened to Ferguson at a crucial juncture. Plucked from Midwestern obscurity in Pittsburgh and thrust into a playoff push in Seattle, he initially performed well before running into a spate of poor performances in late August and early September. In a tight postseason race, that was that — Ferguson didn’t get many leverage opportunities for the remainder of the season, and his brief playoff work went terribly. Brought in to close down a seven-run lead in the ninth inning of ALDS Game 3, Ferguson allowed three runs without recording an out, requiring Dan Wilson to throw Andrés Muñoz on a day that he could’ve secured some crucial rest. It cannot be great for a reliever to get shelled on a big stage in his final moments before hitting the free market.

For most of his Mariners tenure, Ferguson was treated like a member of the B team, deployed mostly in losing efforts. Will the Reds, themselves a recent playoff club, trust him to handle leads in close games? It’s sort of on the edge. RosterResource sees Ferguson as the fourth arm out of the pen, behind Emilio Pagán, Tony Santillan, and Graham Ashcraft. Astute readers will note that all three of those guys throw baseballs with their right arm, and so Ferguson will assume the mantle of Most Trusted Lefty, prying that loosely held title from Sam Moll’s fingertips.

Like Travis Henderson in 1984’s Paris, Texas, Merrill Kelly left his home, wandered across the desert, and ultimately realized he needed to head back where he came from. On Sunday morning, Ken Rosenthal reported that Kelly was finalizing a two-year, $40 million contract to return to the Arizona Diamondbacks.

Kelly is as Arizona as a cactus in a backyard pool. (Meg tells me they typically aren’t actually in the pool, but you know what I mean.) He went to high school in Scottsdale, a couple dozen miles northeast of Chase Field. After a stint at Yavapai Community College, he transferred to Arizona State to finish up his college career. Drafted by the Rays, Kelly shuttled off to Korea for four years in his 20s before returning to make his MLB debut for the Diamondbacks in 2019. He has spent his entire major league career in Arizona, save for a two month sojourn to Texas following a midseason trade at the 2025 deadline. Perhaps scandalized by Arlington’s complete lack of any public transit — not even a single bus line! — he kept his time with the Rangers short. In Phoenix, he’ll return as the presumptive ace at the unlikely age of 37 and with the unlikely fastball velocity of 91.8 mph.

There will be analysis of Kelly’s game to come, but his appeal is easily summarized: The guy can just pitch. Yes, his fastball sits about three ticks slower than the average right-handed pitcher. And sure, his stuff metrics are nothing to write home about. But even with these clear limitations, Kelly succeeds because he does two extremely important things: He locates the ball, and he makes it impossible for hitters to guess which pitch is coming. Read the rest of this entry »

Rest in peace, starting pitcher Ryan Helsley (November 23, 2025 — November 29, 2025.) Last Sunday, a trio of staffers at The Athletic reported that the Tigers, among other teams, were interested in converting Helsley into a starter. Even by the open-minded modern standards of reliever-to-starter conversions, this seemed like a stretch. As Michael Baumann noted when he pondered the possibility, Helsley’s arsenal, comprised almost exclusively of four-seamers and sliders, is about as limited as it gets, and his extreme over-the-top arm angle leaves little room for projection.

On Saturday afternoon, Helsley’s illustrious starting career came to a close. ESPN’s Jeff Passan reported that the Orioles and Helsley had agreed on a two-year, $28 million pact, with an opt-out after the first year. According to Passan, Baltimore expects Helsley to handle the closer job.

Given the Orioles’ competitive ambitions and their considerable payroll space, they were all but a lock to spend a little cash on a backend reliever. President of baseball operations Mike Elias said as much earlier in the offseason, telling reporters that they were working to acquire an “experienced ninth-inning guy.” Following a season in which their bullpen delivered a 4.57 ERA, their top internal options to handle the late innings were Keegan Akin and Kade Strowd — fine pitchers, but not the leverage arms of a team with division-winning aspirations. After swinging a trade for setup man Andrew Kittredge in early November, Baltimore landed its “experienced ninth-inning guy” in Helsley.

Whether he’s up for the task is a reasonable question. After three straight dominant seasons with the Cardinals — book-ended by All-Star selections — Helsley had himself a nightmarish 2025, particularly after St. Louis traded him to the Mets at the deadline; he had a 7.20 ERA and a 5.19 FIP with New York after posting a 3.00 ERA and a 3.55 FIP before the trade. His 89-mph bullet slider was as effective as ever, racking up a 41.6% whiff rate and staying off barrels, but the fastball got rocked. In an interview with The Athletic’s Katie Woo a few days prior to his signing, he gave his theory for why his season went off the rails.

“I felt great, and the Mets’ models showed I was actually having the best stuff of my career, so it didn’t make sense for me to struggle as bad as I did,” Helsley told The Athletic. “But I was being really predictable in certain counts. It was almost a double-confirmation for hitters. They see it with their eyes, and they also had a stat behind it saying I’m more likely to throw this pitch in a certain count. It just gave them that much more comfort in the box, and more conviction.”

When hitters put his fastball in play, they slugged .667. And they had no issues putting it in play. His 17.8% four-seam whiff rate ranked in the 26th percentile of all pitchers with at least 300 fastballs thrown, surrounded by names like Jake Irvin, Miles Mikolas and Bailey Ober. That’s not ideal company.

Assuming his slider is fine, the merit of the Helsley deal boils down to whether his triple-digit fastball is still a good pitch. The way I see it, there are three possible explanations for its poor performance in 2025. The first is that Helsley was tipping with some sort of visual cue. Helsley told Woo that he believed his hand position “as he was becoming set” revealed whether the pitch would be a fastball or a slider.

“It was pretty obvious,” Helsley told The Athletic. “I’m not the greatest at (spotting pitch tipping), and even I could see it (on film with) the majority of the pitches.”

For whatever it’s worth, it didn’t look that obvious to me. For those on the public side, pitch-tipping analysis often looks like paranoid pattern-matching, like Charlie Day’s Pepe Silvia red string board. There’s little from the center field cameras, at least, that makes it clear. Here’s Helsley’s setup on a fastball that Harrison Bader launched 109 mph to the pull side:

And here is the previous pitch, a slider. Do you see any difference in the setup? To me, there’s no there there.

Here they are right next to each other:

(Helsley changed his setup after this game for the rest of the season, bringing his hands down and holding the ball closer to his body. The results weren’t much better; as Helsley himself said in that interview, it’s hard to make an in-season adjustment.)

While the physical tipping evidence is ambiguous, the count-level predictability is pretty clear-cut. In a broad sense, Helsley maintained a roughly 50/50 usage of his slider and fastball, occasionally tossing in a curveball as a wrinkle. But looking at the overall usage patterns belies the predictability of his pitch selection.

In 0-0 counts, Helsley opted for the heater 57% of the time. In deep hitter counts (2-0, 3-1, and 3-0), that leapt to 75%. Heavy fastball usage in these contexts is somewhat excusable, but Helsley’s full count approach underlined his reliance on the heater in tight spots. Of the 50 pitches thrown in 3-2 counts, 37 (74%) were four-seamers. (Perhaps another reason Bader smashed that 3-2 heater into the stratosphere.)

A similar story could be told with the slider. Heavy slider use in two-strike counts is to be expected, but even in 1-1 counts, Helsley threw it 72 times in 99 opportunities. For a pitcher with essentially two pitches, this type of predictability is lethal, no matter the nastiness of the stuff.

If Helsley’s ineffectiveness comes down to pitch-tipping and count issues, the Orioles have good reason to be confident in a bounce back. But if his stuff is starting to decline, they may have a problem on their hands.

Is there evidence this is the case? If you squint, maybe. Helsley broke out in 2022 with a superhuman 39.3% strikeout rate while tag-teaming the closer role with Giovanny Gallegos. The breakout was fueled by a massive velocity jump — from 2021 to 2022, Helsley’s fastball gained over two ticks, jumping to an average of 99.6 mph. In 2025, that dropped all the way down to… 99.3 mph.

The case for Helsley’s fastball losing its juice, then, would need to be about something other than velocity decline. Here, there is a bit more to latch onto. In that 2022 season, Helsley’s average arm angle on his four-seamer was around 52 degrees. By 2025, that had climbed all the way to 62 degrees with no concurrent improvement to the pitch’s vertical movement.

A fastball’s effectiveness can be largely explained by its vertical movement relative to its release point; more movement from a lower release or lower arm angle makes it tougher for a hitter to pick up. Because the excellent induced vertical break (18 inches) on Helsley’s fastball now comes from a more “vertical” arm angle, it doesn’t have the same deceptive qualities. Once near the top of the scale in terms of Alex Chamberlain’s dynamic dead zone measurements, his fastball has declined to merely “very good.” If Helsley needs to keep hiking his arm angle up each year to maintain the same level of induced vertical break, that could start to look like a concern.

As it stands, this seems to be more of a minor concern than a red flag. The stuff models on FanGraphs — Stuff+ and PitchingBot — both still consider Helsley’s fastball to be a well above-average pitch, even if they agree that the quality has declined slightly from 2022 or 2023. He’s sitting 99 mph, after all — even with poor shape, a four-seamer with that velocity should still play.

Overall, I’m inclined to say that both sides found a good deal here. The reliever market is the first of any position group to take shape in this early offseason, with both Phil Maton and Raisel Iglesias inking deals prior to Helsley. Iglesias is older, but received $16 million for a single year’s work; Maton, a solid middle reliever, got two years and $14.5 million. If this is the range for the second-tier relievers, and if the three top guys — Edwin Díaz, Devin Williams, and Robert Suarez — are in line for a good chunk more, Helsley’s signing starts to look pretty reasonable for the Orioles, especially because he is only one year removed from being in that elite group. For Helsley, it’s another shot at ninth-inning duty, with a chance to hit the market again next offseason, assuming all goes well.

From 2022-2024, Helsley ranked fourth among all relievers in FIP. His stuff is essentially the same as it was during that run. Assuming he sorts out the tipping issues and gets a little less predictable in certain count contexts, the Orioles just signed a high-end closer at an eminently reasonable price – even if it only proves to be for one year.

During an introductory press conference for outfielder Brandon Nimmo this week, Rangers president of baseball operations Chris Young somehow expressed both confidence and uncertainty about his newest acquisition. Nimmo, he said, would handle right field for the Rangers in 2026, though he didn’t sound too sure about it.

“We’re not 100 percent committed to [Nimmo in right],” Young told reporters on Monday. “I think it’s likely where he’ll play, but [those are] conversations that we’ll have with Brandon, with [manager] Skip [Schumaker] and with Wyatt [Langford], and really making sure that we understand all aspects of this and where they’re most comfortable. I do think we have three very good, talented, very talented outfielders. At the outset, I think it’s likely Brandon plays right, but I think that’s a further conversation.”

There are a number of considerations here. Nimmo, at this phase of his career, is almost certainly best in left field. His knees are jacked up; his arm is noodle-adjacent. Evan Carter nominally profiles as a center fielder, but injuries have kept him off the field for much of the last two seasons; it’s possible a corner could be the best way to ensure his availability. Langford’s known right field experience is limited to a single game for the 2022 Peninsula Pilots of the collegiate summer Coastal Plain League.

In my view, there’s only one way to sort this mess out: Commit to playing Langford in center. Read the rest of this entry »

Technically, the starting gun for the 2025-26 offseason already fired. Back on November 5, Leody Taveras signed a one-year, $2.1 million contract with the Orioles, though you’d be forgiven for missing that news, seeing as it came just days after a transcendent World Series and didn’t even merit a writeup on this august website. So let us consider November 16 the official first day of the offseason. On Sunday evening, Jeff Passan reported that first baseman Josh Naylor and the Seattle Mariners were “finalizing” a five-year deal. (On Monday evening, Ken Rosenthal reported the terms: five years, $92.5 million.) In estimating Naylor’s contract for our annual Top 50 Free Agent ranking (he checked in at no. 11), Ben Clemens anticipated a four-year, $100 million deal, while the median crowdsource projection was four years and $80 million.

The first real move of the offseason, fittingly, is perhaps its most predictable. From the day their season ended, the Mariners’ front office shared its desire to bring Naylor back to the Pacific Northwest.

“It was a great fit and it’s definitely a priority for us this offseason — if not one, I don’t know what else would be, he’s no. 1 right now,” Mariners general manager Justin Hollander told MLB Network Radio on the first day that free agents were allowed to sign with other teams. “I don’t really see a reason, there’s no advantage to hiding the ball, to telling people, ‘It was just fine.’ It wasn’t just fine. It was awesome. It was a great fit for the two months, and we’d like to make it last a lot longer.” Read the rest of this entry »

It could not have started worse. Yoshinobu Yamamoto’s first pitch of NLCS Game 2 was a 97-mph four-seam fastball to Jackson Chourio, the Brewers’ powerful leadoff hitter. Chourio promptly hammered it 389 feet into the Dodgers’ bullpen. It landed like a signal to the relievers milling out on the berm: Be alert, you might be needed sooner than you thought.

They would not be necessary. It’s hard to imagine a better pitching performance than that of Yamamoto’s teammate, Blake Snell, who delivered 10 strikeouts over eight innings the previous night. But Yamamoto managed to one-up him.

Over 111 magnificent pitches, Yamamoto rendered the Brewers’ bats rudderless, holding them to that single run over a three-hit complete game. It was the first in the playoffs in eight years, and it certainly offered one possible solution to the Dodgers’ bullpen woes: What if you just didn’t need those guys? Read the rest of this entry »

The margins were so thin on this first day of the 2025 postseason. Aces shoved, the games stayed close, and the high-leverage innings piled up; the first six teams to play combined for just 11 runs. At this unusual time of the year — when the patient regular season gives way to a best-of-three all-out sprint, when managers summon a flame-throwing reliever at the first sign of trouble — even a momentary slip in form can spell the end of the contest. And so it was for Hunter Greene in the third inning of the Dodgers’ (mostly) emphatic 10-5 win over the Reds in Game 1 of their NL Wild Card Series showdown. Greene faltered, the Dodgers capitalized, and Los Angeles gained a crucial series lead.

It seemed like this last game of the day would be yet another tightly contested pitchers’ duel. The Dodgers hurler, Blake Snell, headed into Tuesday night’s matchup in fine form, spinning a 2.01 FIP in September. He held up his end of the bargain, striking out nine Reds over seven innings, bullying the heavily right-handed lineup with hard heaters in and feathery changeups away. But for about 10 minutes, Greene was a touch off, and that was that. The Reds never really got back into the game after that four-run third inning, even as the shaky Los Angeles bullpen briefly stirred up a scene in the late innings. Read the rest of this entry »

Every once in a while, I take a peek at the Kirby Index leaderboards. In August, the expected names that populated the top of the rankings: Kevin Gausman, Trevor Rogers, and Jacob deGrom. Similarly, the bottom featured stereotypically wild hurlers: Joe Boyle, Luis Gil, Freddy Peralta, and… Janson Junk???

If you’re familiar with Junk, it’s most likely due to his excellent command: Among all starters with at least 70 innings pitched this season, his 3.0% walk rate ranks as the lowest. (In an excellent interview with David Laurila last month, Junk talked about training his command at Driveline over the winter.) Seeing Junk in last place on this leaderboard was like spotting a polar bear in Arlington, Texas — in other words, a sign that something was seriously amiss.

By all four components of the Kirby Index, Junk ranked poorly. But his vertical release point was particularly inconsistent, sitting dead last among pitchers in the sample. In my article from last year introducing the Kirby Index, which I linked to above, I found that the ultimate location of the pitch is dictated almost entirely by release angles and release points. It follows that pitchers with inconsistent release points exhibit poor command. How was Junk varying his release point so frequently and still throwing so many strikes? Read the rest of this entry »

Watch this play. What do you notice?

Here’s what I see: Brooks Lee lofts a soft fly ball 248 feet from home plate. Chandler Simpson circles it but loses a bit of momentum by the time it lands in his glove. Twins third base coach Tommy Watkins sends the not-particularly-fast Trevor Larnach (18th-percentile sprint speed). Shallow fly ball, slow runner, close play at the plate — Larnach slides in just ahead of the throw. It’s an exciting sequence, and I’ve missed an important part of it. Read the rest of this entry »

Straight away, I wrote Jacob Lopez off. Even as he strung together three incredible starts in June — 32% strikeout rate, one run allowed over 19 innings — I couldn’t bring myself to think it actually meant anything. A 27-year-old lefty with hardly any prospect pedigree and so-so command throwing 90 mph dead zone fastballs? Small sample weirdness, nothing to see here.

It’s harder to dismiss Lopez these days. Once again, he’s on an infernal heater, this one even more scalding than the previous iteration. His last three starts: five innings, no runs, five strikeouts against the Diamondbacks; 7.2 innings, no runs, 10 strikeouts against the Nationals; seven innings, no runs, nine strikeouts against the Rays. That’s a 34.3% strikeout rate and a 0.98 FIP in a 19.2 inning sample.

Some of this is the quality of the opposition; the Rays and Nationals have been among the worst offenses in baseball over the last month or so. But the overall sample is getting uncomfortably significant. Over his 84.2 innings pitched this year, Lopez holds a 28.9% strikeout rate, eighth — eighth! — among all pitchers (minimum 80 innings pitched). He’s striking out more hitters than Paul Skenes, Jacob deGrom, and Spencer Strider. Read the rest of this entry »