Overreaction Season and Quinn Priester

Alas, baseball season is upon us and one of my favorite long-standing traditions has carried on yet another year. This tradition isn’t the pre-game anthem, the fabled seventh inning stretch, or the drunken “Go Cubs Go” sing-along after a Cubs’ home win. Overreaction, rather, stands as my favorite early baseball season tradition. Be it an earlier-than-expected trade, a poor win-loss record, or a 2nd standard deviation performance, fans always have a special ability to throw perspective out the window. The Quinn Priester trade between the Brewers and Red Sox has followed this special tradition to a tee.

The Red Sox traded Priester to the Brewers for Yophery Rodriguez, John Holobetz, and a draft pick. To the everyday reader, that seems like two relatively unknown prospects and a draft pick for Quinn Priester. Baseball discourse prefers to put this trade into the perspective of Quinn Priester for the Brewers #14 prospect, their 2024 5th round pick who has overperformed thus far in affiliated ball, and a valuable compensation round draft pick. To add fire to the Brewer fan frustration, Priester has posted an ERA north of 5, negative WAR, and a putrid 1.66 WHIP. For many, the story ends here. The Brewers have been fleeced, anger ensues, and the past good deeds of 2024’s executive of the year Matt Arnold are thrown to the wayside. 

The overreaction news cycle often has me often returning to Amos Tversky and Daniel Kahneman’s 1974 paper, Judgment Under Uncertainty: Heuristics and Biases. This article isn’t a deep dive into the concepts covered by Tversky and Kahneman, but their insights lend well to assessing roster moves from a bird’s eye view. Tversky and Kahneman write, “... suppose one is given a description of a company and is asked to predict its future profit. If the description of the company is very favorable, a very high profit will appear most representative of that description; if the description is mediocre, a mediocre performance will appear most representative. The degree to which the description is favorable is unaffected by the reliability of that description or by the degree which it permits accurate prediction. Hence, if people predict solely in terms of the favorableness of the description, their predictions will be insensitive to the reliability of the evidence and to the expected accuracy of the prediction.”

On paper, the Brewers trading their #14 prospect, past 5th round pick, and 2025 comp pick for a struggling starter who hasn’t found footing at the major league level yet seems unfavorable to say the least. However, if that description gets reworded to: the Brewers trade a prospect they were lower than market on, a 5th round pick who has a limited sample size of success, and a 2025 comp pick for a pitcher with the upside to be a top 50 pitcher in the game, the trade’s favorability seems noticeably different. 

What’s especially challenging about assessing trades from a public perspective is identifying what teams know that we don’t. The Brewers have followed Yophery Rodriguez for years - they know his work ethic, his clubhouse fit, trends in bat speed and path, and strength and conditioning progress. They also have more data on John Holobetz at the college level and the changes he has made since playing in pro ball. Who's to say that the public fully understands the value of these players? 

Judging trades is a game of judging uncertainty and description accuracy. Our public information of Rodriguez, Holobetz, and a comp pick hasn’t changed much since the deal. We have learned more about Priester after six starts for the Brewers at the major league level than we have any of the other pieces in the deal. In this article, I aim to put my Cubs fan bias aside and make a bull case for Priester becoming the front of the rotation starter that the Brewers hope he can become.

Priester features a five pitch mix that includes a sinker, cutter, slider, curveball, and changeup. The sinker stands out as Priester’s most impressive pitch, boasting a Stuff+ of 105 which sits one standard deviation above the league-wide 92.5 sinker Stuff+ average. This pitch serves as the lynchpin of Priester’s arsenal, leading the way in usage so far in 2025. Priester’s sinker sports a 67.3% first pitch strike percentage, well above the sinker average of 58.7%. That mark is good for 5th among all starting pitchers in baseball behind the likes of Chris Bassitt, Logan Webb, Luis Severino, and Ben Lively. 

In terms of shape, Priester’s sinker resembles extremely similar characteristics to the sinker of Clay Holmes, a pitcher lauded for his ability to produce grounders while limiting barrels. Holmes’ sinker sports a Stuff+ of 102 compared to Priester’s 105. Holmes stands at 6 '5 and throws from a 45.8 degree arm angle while Priester measures 6' 3 and sports a 45.9 degree arm angle. The similarities don’t end there. According to Alex Chamberlain’s pitch leaderboard, Priester and Holmes’ sinkers carry nearly identical -3.1 and -3.4 vertical dead zone deltas while having the same +0.1 horizontal dead zone delta, meaning they create a similar amount of unexpected movement from the hitter’s perspective. Similar dead zone deltas, height, arm angle, and Stuff+ leads me to believe that Priester’s sinker results should be able to line up closely with Holmes’.

Comparing Priester and Holmes’ sinkers, their zone, contact, and swing rates have been about 5% apart from each other thus far with Holmes leading the way in each category. Holmes also has a CSW% 7% better than Priester. We start to see further separation in results with Holmes locating his sinker in the shadow zone 8% more than Priester while locating in the heart of the zone at the same rate. This discrepancy leaks into putaway% where Holmes outclasses Priester with his 26.7% putaway rate contrasted to Priester’s measly 11.6%, good for 7% below league average on sinkers.

Poor location quality has led to poor BBE quality for Priester where his Barrel% is 3x Holmes’ 2.3% and his xWOBAcon sits at .391, a mark far exceeding Holmes’ .342. These differences come with both pitchers posting a nearly identical 104.8 and 105.2 90th percentile EVs on sinkers, pulled fly ball rates of 2.3% and 0%, and average launch angles both south of 3 degrees. I believe these stark differences are mostly due to Priester possessing much worse command across all pitches while also misusing secondary offerings.

Priester’s Location+ reaffirms his purported command concerns with his 88 mark being below league average and off the pace of Holmes’ 102. Even more troubling, Priester’s 88 continues a worrisome trend in which Priester’s command has gotten worse each year since his first majors stint in 2023 with the Pirates where his Location+ matched Holmes’ 102. Although a downward trend will always be cause for concern, it’s good to know that we have a reference point for success in regard to command. 

Here’s two sinkers both against lefties in American Family Field thrown by Priester. The Pirates version is the 2023 Priester which saw a positive 102 Location+ throughout the year and the Brewers Priester is the one currently struggling.

I tried to match these pictures at three points - set at the stretch, the top of the leg kick, and waist facing home plate. At set, Priester looks to have ditched a more bent back leg while also pulling his hands closer to his body with his feet closer together. From here, Priester gets set at the top of the leg kick at a much higher point in Milwaukee then he did in Pittsburgh. This higher leg kick, notably, hasn’t increased velocity on his sinker over time. I believe the view from Priester’s waist facing home plate to be the most insightful as his arm angle seems to be getting steeper since 2023. This could be a root cause of Priester’s general control problems. Priester’s mechanics in Milwaukee look like he’s trying to press for positive results, rather than just pitching. A more rigid set up, higher leg kick, and over the top finish all make it look like Priester is less comfortable than he once was.

Not only could Priester’s mechanics use some refinement, his pitch mix could also use a refresher. Priester started the year barely throwing his curveball to lefties and recently threw it around 35% of the time to lefties in his May 2nd start. This has come at the expense of his cutter and changeup. Stuff+ would tell us that ditching his 20% below league average cutter is a net positive, but cutting his changeup usage, his only plus offspeed offering, seems questionable. I believe using his changeup more, especially against lefties, could quell some of the contact concerns with his sinker to lefties. Although the changeup grades well, it’s hard to know its true effectiveness with only 3 BBEs thus far in 2025. His most used offspeed offering, the slider, has been effective so far this year, yielding a .225 xWOBAcon to righties and a .278 xWOBAcon to lefties. 

Priester’s ability to successfully play the east/west game throws him into a category of pitchers like Logan Webb, Michael King, and Clay Holmes. However, what separates those three with Priester is the ability to have one more pitch that can play more vertically. Upon signing with the Mets, we saw the Mets pitching lab notably add a kick-change to Holmes’ repertoire, a pitch that’s already posted a .214 xWOBAcon, one of the best numbers in all of baseball. 

video h/t PitchingNinja

A return to 2023 mechanics paired with a focus on sinker, slider, and changeup usage leads me to believe that Priester can exceed the Brewers’ expected trade value. Statistics can’t quantify what Priester has lacked so far in his career - continuity. After all, Priester is a 24-year-old who hasn’t made an opening day roster and has been on three teams in three years, an irregularity for a first round pick. Given more time in an organization lauded for pitching development, I wouldn’t be shocked to see Priester break through during this season. The negative results are apt cause for concern, but past flashes of upside warrant more grace for a pitcher of Priester’s pedigree. 

Six bad starts is just that, six bad starts. The beauty of baseball fandom is the emotions that come with following a team for 162 games. The days where you yell at your favorite player through a screen makes the day they go succeed in the playoffs that much more rewarding. That’s what keeps us coming back each day to watch the game that consumes our whole summer. However, remember next time when you watch that the description given by the broadcast graphics isn’t all that there is. In 2025, baseball teams, especially ones like the Brewers, have a keen eye for talent and, after all, they didn’t trade for Quinn Priester for just six starts. They’re here to play the long game and develop him further. The right way to do that is as much an art as it is a science, but that’s what makes watching and following these players the emotional rollercoaster that keeps us coming back and overreacting.