When I began writing this piece about Alek Thomas‘ defense, it was in response to the excellence he had shown in the postseason as Arizona’s everyday centerfielder. Since then, an elephant walked into the room in the form of his ninth-inning error in Game 5 of the World Series, and while it didn’t cost the Diamondbacks the title or even the game, it undoubtedly left a bitter taste in his mouth that he’ll likely spend much of the offseason trying to rinse out. But his late-game error was a tragically timed blip on an otherwise excellent performance this October — one that speaks to the specific improvements he’s made to his outfield defense, and how those adjustments have altered his forecast as a big leaguer. So let’s take a look at how Thomas’ defense has evolved since his days as a bat-first prospect, rewinding to this catch in Monday night’s Game 3.

That catch was one of several he made throughout the postseason, which provided Thomas with a national audience to wow with his range in the outfield. The way he covered ground out there played well on TV, too, particularly how he went back on deep balls to center field, sprinting with his head down toward the wall and making mid-route adjustments as needed. But while his wall-banging robbery of what would otherwise have been an RBI double for Mitch Garver was an obvious defensive highlight in its own right, it was also a clear indication of the improvements Thomas has made to his center field defense over the past couple seasons. Read the rest of this entry »

In Game 3 of the Twins/Astros ALDS, the subject of Sonny Gray’s sweeper came up in the broadcast booth. That set the stage for Adam Wainwright to clear up some confusion that dates back a ways, and put forth an answer to the question that has been spinning around the league for a while: What exactly is a sweeper?

Here’s the clip:

Adam Wainwright explains the difference between a sweeper and a slider ? pic.twitter.com/vdtCh9EU6W

— FOX Sports: MLB (@MLBONFOX) October 10, 2023

In just over a minute (and with deftly added pauses for the purposes of game calling), Wainwright covered a lot of ground, first pointing out the shape of the sweeper as compared to a traditional slider, then going on to scratch the surface of how the pitch is thrown and how that impacts its shape. At one point during his spiel, he chuckled at the camera, visibly concerned about how little time he had to explain something so complicated. So with the benefit of a much more flexible word count than he was afforded in the booth, let’s break down Wainwright’s breakdown, beat-by-beat, and see if we can illustrate and expand on what he was talking about by taking a look at some of 2023’s sweepingest pitchers. Read the rest of this entry »

There’s a week at the end of every season when Triple-A welcomes some of baseball’s top prospects for a brief stint at the minor leagues’ highest level before they hang up their cleats for the year (or in many cases, head to the Arizona Fall League). Expanded rosters at the big league level leave a slew of freshly vacated Triple-A roster spots. Meanwhile, the Low-, High-, and Double-A seasons end when there’s still a week left on the Triple-A schedule, creating a sizable pool of lower-level up-and-comers. These prospects, especially the younger ones, are looking to prove themselves capable of standing up to competition beyond what their developmental schedule might otherwise deem appropriate. It’s also a big reason why so many of the following year’s prospect list write-ups include some version of the phrase “He notched a few innings at Triple-A at the end of last season.”

One such prospect this year is Ricky Tiedemann, the young lefty hurler who sits atop the Blue Jays prospect list and currently ranks 18th on our overall Top 100. If that résumé sounds oddly familiar, you may be picking up echos of recent big league debutant Kyle Harrison, who tops the Giants list and is stacked just spot above Tiedemann on our Top 100. The similarities don’t end there, though. Both Harrison and Tiedemann were drafted as teenagers, and both boast a tremendous punchout ability that belies their years, posting strikeout rates above 40% at various points in their young pro careers.

Before I continue, a caveat: Due to a combination of mid-season arm soreness and a short leash when it came to his pitch count, Tiedemann only threw 44 innings in 2023. That’s important to keep in mind, especially considering that Harrison’s lowest innings total in a pro season is more than double that. Tiedemann still has to demonstrate that he’s capable of maintaining his prowess over the type of innings load that Harrison has endured. With that established, let’s dig into how the two young southpaws resemble one another, and more importantly, what sets Tiedemann apart, at least for now. Read the rest of this entry »

There are certain stats that seem likely to always move in tandem. A high walk rate will, almost by definition, result in a high on-base percentage. A low whiff rate seems to naturally beget a high contact rate. But sometimes things don’t line up in the way intuition would dictate.

The other day I was perusing the minor league pitching leaderboards and when I sorted them by swinging strike rate, a crop of standouts topped the list, posting rates higher than 16% (the minor league average is around 12% for pitchers with at least 100 innings pitched). Curious, I re-ordered the list to see how these pitchers stacked up in terms of strikeout rate – a stat my brain assumed would result in a similar list of names, if slightly reordered. To my surprise, however, many of the top-ranked swinging-strike inducers skidded down the list when it was re-sorted by strikeout rate:

This caught me off guard, so I pulled up the major league leaderboards and repeated the same steps, first sorting by swinging strike rate, then by strikeout rate. At the major league level, no pitcher even falls out of the top 30, let alone tumbling as tremendously as some of the top bat-missers of the minor leagues:

It seems like the recipe that whips up minor league pitching success isn’t the same as the one that results in being a bat-missing major leaguer.

So, what gives?

Let’s start with the obvious. Perhaps the clearest difference between pitching in the minors and pitching in the majors is the caliber of the opponents. Specifically, it’s much more difficult to induce a swinging strike on a junky pitch when facing an advanced hitter than it is against a less-experienced minor leaguer. Thus, it stands to reason that in-zone swinging strike rate is a more reliable indicator of the sustainability of minor league results, as it diminishes the impact of a batter being duped. Testing this theory against the major league pitching leaderboard supports this idea, as the list of high-achievers stays relatively constant when sorted by in-zone contact rates.

That logic still holds true when we look to the minor league leaderboards. Indeed, of the 10 pitchers leading the minors in swinging strikes, only two (Drew Thorpe and Yoniel Curet) have in-zone swinging strike rates that are better than their overall mark in that column. And wouldn’t you know it, those are the only two pitchers who stay in the top 10 when the list is instead sorted by strikeout rate. The other three minor leaguers with overall swinging strike rates above 16% (Chih-Jung Liu, Cristian Mena, and Nick Nastrini) all have in-zone swinging strike rates that are lower than their overall swinging strike rates, and each of these pitchers falls by a few dozen spots when the list is re-ordered by K-rate. This illustrates the importance of missing bats in the zone, particularly when it comes to alchemizing whiffs into punchouts.

It also stands to reason that promotion to a higher minor league level would result in a dip in these types of pitching statistics. Assuming, as we do, that it’s easier to fool a Double-A hitter into offering at an unhittable breaking ball out of the zone than it is a Triple-A hitter, then promotion from one level to the next would presumably expose a pitcher’s reliance on chase swings as opposed to those precious in-zone whiffs. Lucky for us, two of the aforementioned pitchers – Nastrini and Mena – are not only in the same org and have virtually identical Double-A stats, but they also received simultaneous Triple-A promotions at the end of August. So, let’s take a look at how they compare and assess what their results might indicate about the sustainability of their minor league success.

Looking at how Nastrini and Mena performed on paper at Double-A makes them seem like virtually the same player. They’re both in the White Sox system, with similar stats in terms of swinging strikes, walks and strikeouts. They also feature the same arsenal – four-seamer, slider, curveball, changeup – and made their Triple-A debuts within a couple days of one another. But within those similarities, there are key distinctions between them that might alter our expectations of them.

Let’s start with how they ended up with the White Sox. Mena was signed for $250,000 out of the Dominican Republic in 2019, and while the start of his pro career was delayed by the pandemic, he was still just 18 when he took the mound for the first time in 2021. Having been largely untested before then, he quickly ascended through the org as part of Project Birmingham and is now the youngest pitcher to reach Triple-A this year. Conversely, Nastrini, who is several years older, was acquired mid-season as part of the Joe Kelly trade with the Dodgers and boasts a more robust track record than Mena, having been a fourth-round pick in 2021 out of UCLA.

In terms of statistics, their walk rates were identical at Double-A, each posting an unsavory 11.3% mark in that column. Their strikeout rates were similar to one another as well, each hovering above 25%, and their swinging strike rates differed by just .1%, with Nastrini’s coming in at 16.5%, and Mena’s at 16.6%. But before we chalk up those similarities to these guys being the same pitcher in different fonts, let’s investigate how they’re producing these numbers and see what we might expect from each going forward.

While Nastrini and Mena feature the same pitch mix, they use their arsenals in very different ways. Mena has long boasted an impeccable ability to spin his curveball, to the point that he’s been tasked with building his arsenal around that pitch. Since turning pro, he’s worked on adding a slider to his mix, and while it’s developed a slightly more distinct shape this season (tighter, with more horizontal action), it still blurs with his curveball, with both pitches acting in similar ways to miss bats on offerings out of the strike zone.

While Nastrini’s breaking balls don’t cause jaws to drop the way Mena’s curveball has throughout his career, their shapes are much more distinct from one another, and there’s roughly 7 mph of velocity separation between them.

Both pitchers throw a changeup between 13-14% of the time, and both favor the cambio against lefties. Nastrini’s changeup has a sharp shape to it, with its velocity and arm-side movement geared at mirroring the movement of his slider, allowing the changeup to work against lefties the way that his slider works against righties.

Mena’s changeup is also most effective when he’s able to play it off of the shape of his slider, in the hopes of getting lefties to flail at it off the plate. Unfortunately, his changeup is much faster than the slider, flirting with 90 mph, and its shape doesn’t feature much horizontal action.

Meanwhile, Mena’s fastball has lost some of its ride, as well as a tick or two of velocity, so it tends to hover in the 91-92 mph band, and without the bat-missing ride, its shape and velocity are too similar to those of the changeup for either pitch to be a reliable in-zone bat-misser.

As a result, Mena’s lukewarm heater has been frighteningly hittable this season, contributing to a very high home run rate for the young hurler. Nastrini’s four-seamer, on the other hand, has been much more successful, with a flatter, more deceptive shape. It’s thrown from a release point that’s more difficult to pick up due to Nastrini’s setup towards the third base side of the rubber. His fastball has maintained a higher average velocity, eliciting significantly more swinging strikes and a more anemic resulting slash line than that induced by Mena’s heater. This in turn has resulted in more whiffs throughout the strike zone, particularly at the top of it, and confirms that Nastrini’s overall swinging strike rate doesn’t rely as heavily on chase as Mena’s does.

That said, Nastrini’s command is worse than Mena’s, as he offers up a greater number of non-competitive wild pitches compared to Mena’s strategic out-of-zone offerings. Their matching walk rates at Double-A were arrived at very differently, with Mena’s coming as a side effect of intentional out-of-zone offerings, whereas Nastrini’s were more indicative of legitimate mistakes. This has held true at the higher level, with both pitchers now a few starts into their time with Triple-A Charlotte. In fact, many of the assumptions that could be drawn from their time at Double-A have come to fruition since their promotion.

In Mena’s first start, only three of his 88 pitches resulted in a swinging strike, due largely to Triple-A batters’ collective ability to lay off his breaking balls. His second and third starts were better in this regard, but he still struggled to induce chase on the outer half against righties, which was a key ingredient in the elixir that allowed his stuff to play up at lower levels. The patience of his opponents has resulted in a relative downtick in strikeouts, along with an uptick in walk rate. He has also given up an inordinate number of hits, due in large part to the hittablity of his heater. Nastrini, on the other hand, has kept opposing bats off his offerings but has struggled to maintain command. His second start with Triple-A Charlotte featured four wild pitches, including one with the bases loaded, which nearly allowed two runs to score when the ball bounced several feet in front of the plate and caromed off the catcher’s gear into the visitors dugout.

It’ll take more than a few starts apiece to get a sense for how Mena and Nastrini adapt to the higher level, but their outings have been in keeping with our expectations so far. Mena is young and athletic enough to hope that he’ll be able to tack additional velocity onto his fastball, while also working to refine the look of his entire arsenal to induce more in-zone whiffs. Expectations-wise, this likely means Mena’s on his way to a big league role at the back of a rotation, with multi-inning relief as a fallback option. Nastrini is more fully developed in terms of the look of his stuff, so his more urgent task will be to refine his command, such that his entire repertoire can play to its potential. As such, his ceiling is higher, and a spot near the front of a rotation is attainable if the command piece falls into place. Otherwise, he has the look of an impactful late-inning reliever.

All in all, if either Mena or Nastrini hope to remain atop the swinging strike leaderboard at Triple-A and beyond, there are key improvements to be made and flaws to be addressed, and despite their seeming similarities, their respective flaws (and necessary improvements) are distinct from one another. While it seems neither is likely to emerge as the next Spencer Strider, they both have a good shot at firming up an important big league role within the next season or two.

The Oakland A’s have not been shy about calling up their top prospects this season, including a slew of the most highly-ranked young players in their system. Many of those prospects have already begun to sculpt the narrative of their early big league careers, to largely disappointing results. Mason Miller dazzled in his first few outings, but was felled by injury soon thereafter. Kyle Muller has bounced between the majors and Triple-A, with a meager mid-teens strikeout rate and an ERA above 7.00 at both levels. Esteury Ruiz has been as spectacular as expected on the basepaths, but his Triple-A offense was a mirage that has dissipated in the majors. And while Ken Waldichuk’s stuff seemed noteworthy in the lead up to the season, his walk rate has ballooned and his fastball was at one point measured by Statcast as the worst in the league, at 16 runs worse than average. As of now, to borrow a phrase, he’s just Ken.

This past month has seen the promotion of three more of Oakland’s promising young prospects: Tyler Soderstrom, Zack Gelof, and Lawrence Butler. The most recent of those promotions was Butler, who joined the A’s major league roster on August 11 after tamping down his strikeouts and finding himself on an ultra-fast track (he started the season at Double-A). With just a handful of games under his belt, it’s too soon to read much into his performance. Soderstrom and Gelof, meanwhile, both debuted in mid-July. And while Soderstrom is the more highly ranked prospect, his bat has been too quiet to make up for his strikeouts at the big league level. Instead, it’s Gelof whose name is currently accompanied by a string of fire emojis in the Baseball Savant search bar. Read the rest of this entry »

Below is an analysis of the prospects in the farm system of the Oakland Athletics. Scouting reports were compiled with information provided by industry sources as well as my own observations. This is the third year we’re delineating between two anticipated relief roles, the abbreviations for which you’ll see in the “position” column below: MIRP for multi-inning relief pitchers, and SIRP for single-inning relief pitchers. The ETAs listed generally correspond to the year a player has to be added to the 40-man roster to avoid being made eligible for the Rule 5 draft. Manual adjustments are made where they seem appropriate, but I use that as a rule of thumb.

A quick overview of what FV (Future Value) means can be found here. A much deeper overview can be found here.

All of the ranked prospects below also appear on The Board, a resource the site offers featuring sortable scouting information for every organization. It has more details (and updated TrackMan data from various sources) than this article and integrates every team’s list so readers can compare prospects across farm systems. It can be found here. Read the rest of this entry »

Below is an evaluation of the prospects in the Oakland Athletics farm system who readers should consider “imminent big leaguers,” players who might reasonably be expected to play in the majors at some point this year. This includes all prospects on the 40-man roster as well as those who have already established themselves in the upper levels of the minors but aren’t yet rostered. I tend to be more inclusive with pitchers and players at premium positions since their timelines are usually the ones accelerated by injuries and scarcity. Any Top 100 prospects, regardless of their ETA, are also included on this list. Reports, tool grades, and scouting information for all of the prospects below can also be found on The Board.

This is not a top-to-bottom evaluation of the A’s farm system. We like to include what’s happening in minor league and extended spring training in our reports as much as possible, since scouting high concentrations of players there allows us to incorporate real-time, first-person information into the org lists. However, this approach has led to some situations where outdated analysis (or no analysis at all) was all that existed for players who had already debuted in the majors. Skimming the imminent big leaguers off the top of a farm system will allow this time-sensitive information to make its way onto the site more quickly, better preparing readers for the upcoming season, helping fantasy players, and building site literature on relevant prospects to facilitate transaction analysis in the event that trades or injuries foist these players into major league roles. There will still be an A’s prospect list that includes Gunnar Hoglund, Max Muncy, Daniel Susac and all of the other prospects in the system who appear to be at least another season away. As such, today’s list includes no ordinal rankings. Readers are instead encouraged to focus on the players’ Future Value (FV) grades. Read the rest of this entry »

If Oakland Coliseum is indeed “baseball’s last dive bar,” as has often been asserted, then it must have one hell of a booking manager. Let’s not forget, after all, that this dive bar has a stage. And yes, that stage may be a bit far from the audience, and sure, it is housed in a hulking cement behemoth that shares a BART station with the airport, and fine, it might be subject to the occasional rodent or plumbing issue. But it still draws the same big names as other, glitzier venues. The Coliseum’s dinginess might generate headlines, but lately I’ve been struck more by the unique backdrop it offers attendees for seeing the major’s biggest names.

When I used this metaphor to describe my experience at an August 9 Shohei Ohtani start at the Coliseum, a friend likened it to seeing Metallica play an unannounced show a few years ago at The Metro, a venue just a stone’s throw up Clark Street from Wrigley Field, with a capacity of 1,100. You may remember this early-August Ohtani outing: one of those Tungsten Arm games – unremarkable but for the home run he launched into the right field bleachers and the win he secured, allowing him to reach the Babe Ruth milestone of recording 10 wins and 10 home runs in a season, though Ohtani’s home run total for the season had long eclipsed Ruth’s. The vastness of the stands only emphasized how few people I was sharing my baseball viewing experience with.

The next day, I followed up that major league masterclass with a Low-A day game in the uncovered San Jose grandstand, watching a teenager struggle to throw strikes under the blazing sun. If Ohtani at the Coliseum is Metallica at the Metro, then this game, where I went to watch prospects from the San Francisco Giants organziation, was sitting in on a garage band rehearsal. Low-A is an altogether different brand of baseball, where tweaks are made every day – sometimes even mid-game – in the hopes of tapping into young players’ potential. Read the rest of this entry »

These are notes on prospects from Tess Taruskin. You can read previous installments of our prospect notes here.

Lisandro Santos, LHP, Atlanta Braves
Level & Affiliate: High-A Rome Age: 23 Team Rank: TBD FV: TBD
Line: 3.1 IP, 3 H, 4 R, 10 K, BB

Notes
Santos recorded 10 outs on Thursday night, all by way of the strikeout, as he continued a dominant beginning to his 2022 season at High-A Rome. Notching double-digit strikeouts in relief suggests a remarkable outing worthy of top marks. But much like many a crab cake, it turned out there was a bit too much Mayo in the mix for this performance to quite hold together. Santos’ dominance happened to coincide with Top 100 prospect Coby Mayo’s first multi-home run game of the season. Mayo sent a pair of two-run knocks out, punishing Santos by plating the only other baserunners he allowed on the night.

So far this year, Santos has fanned 41 of the 80 total batters he’s faced, against just seven walks. His fastball still sits in the mid-90s and touches 96 mph, as has been the case for the past several years. He pairs it with a high-80s slider with occasional depth that he throws from a consistent arm slot. Much of his effectiveness comes from his ability to hide the ball. Santos sets up on the far first-base side of the rubber from an exaggeratedly closed stretch. His delivery then features a long arm action and a very short stride, with his arm whipping around from a high slot and slinging across his body, sending him spinning towards third base. The video feed for Santos’ Thursday performance was less than ideal for evaluation, but it does make clear his short stride. Read the rest of this entry »

These are notes on prospects from Tess Taruskin. You can read previous installments of our prospect notes here.

Cade Cavalli, RHP, Washington Nationals
Level & Affiliate: Triple-A Rochester Age: 23 Overall Rank: 78 FV: 50
Line: 5.2 IP, 4 H, 2 R, 6 K, BB, HBP

Notes
Cavalli was dominant over his first few frames on Wednesday, dealing first-pitch strikes to most of his opposing batters and sending them down in order until a weak, bloop single in the fourth. His command faltered later in the game, and he allowed the opposing lineup to string together a few hits, then issued a couple of free passes (one walk, one HBP) and was pulled before he could get himself out of the sixth inning.

You might think that he plowed his way through the order the first couple of times by way of a whirlwind of whiffs – he did, after all, lead the minors in strikeouts in 2021. But many of those Ks were accrued in the early part of last season, as Cavalli began his rapid ascent through the Nationals system. He had a whopping 44.9% strikeout rate in his seven High-A games, then made 11 Double-A starts and fanned 32.9% of those opponents. But when he reached Triple-A for a six-start stint to close out the season, his strikeout rate dipped significantly, with the more advanced batters keying in on heaters that would’ve blown by bats at the lower levels. Read the rest of this entry »