Brewers: Taking a Statistical Deep-Dive into Bryse Wilson's Career-Altering 2023 Season

On January 4th, 2023, the Milwaukee Brewers acquired RHP Bryse Wilson from the Pittsburgh Pirates for cash considerations after he was designated for assignment. This move to acquire Wilson came amongst a flurry of other pitcher acquisitions, with the Brewers acquiring Javy Guerra, Elvis Peguero, Tyson Miller, Janson Junk, Joel Payamps, and others during the 2022-23 offseason.

After being selected by the Atlanta Braves out of high school in the 4th round of the 2016 MLB Draft, Wilson cruised through the minor leagues, making his MLB debut at age 20 in 2018. Wilson was ranked as high as #80 on Baseball America's top 100 list heading into the 2019 season and was ranked as the #6 Braves prospect by MLB Pipeline.

Wilson battled adversity in Atlanta, pitching to a 5.90 ERA in 23 appearances with Atlanta over parts of four seasons, and saw his minor league options dry up quickly as he struggled to stay on the big league roster. During the 2021 season, the Pirates decided to take a chance on his prospect pedigree and acquired him at the trade deadline for Richard Rodriguez.

Wilson did not see a big jump he was hoping for after moving to Pittsburgh, as he posted a 5.37 ERA in his two seasons there. He would see good run at the big league level in 2022, though, making 20 starts over 25 appearances and putting up 115.2 innings over the season.

After being non-tendered at the end of 2022, the Brewers decided to acquire Wilson and see if they could maximize the potential that Atlanta saw when they selected him so high in 2016. In order to do so, the Brewers and Wilson needed to make some changes to different areas of his game, and they worked with him to do just that.

What did Bryse Wilson change going into 2023?

After Wilson arrived in Milwaukee, the Brewers and Wilson combined to make two big-time adjustments: mechanical tweaks to his delivery and pitch usage.

Mechanically, tweaks have been made to each individual pitch in his arsenal by release point, but his extension has stayed relatively similar (6.5 ft in 2022 to 6.6 ft in 2023). These changes have been made to affect the break and spin on his pitches and for some, have even affected velocity.

Wilson's cutter has seen the most change from a mechanical perspective, as his vertical release point has shifted from 5.21 feet to 5.62 feet, while his horizontal release point went from -2.51 feet to -2.99 feet. This small mechanical tweak allowed his cutter to gain 3 extra MPH, while gaining an extra inch of arm-side movement and reduced downward movement by over 5 inches. The cutter also gained an average of 80 RPMs of spin. This change effectively gave his cutter a tighter, slider-like movement compared to his more downward-breaking cutter of 2022.

Along with the cutter, Wilson's four-seamer also gained an extra 77 RPMs on average after shifting his release point. His sinker gained almost 90 RPMs on average while gaining about two inches of vertical movement and losing just under two inches of horizontal movement, making it easier to throw for a strike. Finally, his curveball gained over 190 RPMs and 2 inches of vertical movement, while also gaining 2 MPH in velocity.

All of these factors work together to give Wilson a much more complementary pitch mix, with each individual pitch better playing off of each other. After necessary mechanical tweaks were addressed, the usage of these pitches also needed to be changed heavily.

Coming into the 2023 season, Wilson was seen as mostly a sinker-baller pitcher who relied on a high usage of his fastball to force contact on the ground, along with using five other offspeed or breaking pitches. Wilson's sinker and four-seamer combined to be used 56.5% of the time, his curveball was used at 13.6%, slider at 11.1%, his changeup at 9.5%, split-finger at 5.4%, and finally, his cutter was used at 3.9%.

In 2022, Bryse Wilson only had two pitches with a positive run value (effectively, how good a pitch is at limiting runs). His sinker and cutter posted run values of 2 and 1, respectively. All five of his other pitches were below average or average, with his four-seamer and changeup both giving -10 run value, his slider and curveball coming in at -6 and -3, and his splitter at exactly zero run value. These factors combined to give Bryse Wilson the worst pitcher run value in all of baseball last season, at -27.

The Brewers also went to work on finding the best pitch mix for Wilson to carry into 2023. This pitch mix has seen a steep decline in diversity, but a large increase in productivity. His cutter and sinker are both used just above 34%, while his four-seam fastball has been used at 16.1%, and his curveball at 14.1%. His changeup and split-finger have been thrown 8 total times the entire season, and his slider has been cut entirely.

The run value of his pitches improved heavily in 2023, with every pitch but his sinker taking a step forward. The cutter and four-seam fastball both shot up in run value, with the cutter producing a run value of 8 and the four-seam fastball going from a -10 run value last season to a +5 in 2023. His curveball went from below average to exactly average at zero, and his sinker did take a dip, moving from a +2 run value to -1.

The success of Bryse Wilson's cutter has been a big reason for his breakout. The Brewers saw Wilson's cutter put up season-high numbers in K%, BAA, wOBA, Whiff %, and hard-hit rate in 2022 and wanted to see it used more. Along with the uptick in usage, it has become a much more successful pitch during the 2023 season compared to when he started throwing it in 2022.

For a better look at the difference Wilson has made with his cutter this season, I'll start with a video of one of his cutters from 2022. This was a cutter thrown to Yadier Molina in April of 2022. Notice the break of his pitch, and how it looks more like a changeup than a cutter. According to Baseball Savant, this pitch came in at 85.3 MPH, spun at a rate of 2102 RPMs, and broke 33 inches vertically while breaking 1 inch horizontally.

In 2023, Wilson and the Brewers went to the drawing board and reimagined his cutter. This strike thrown to old friend Esteury Ruiz shows exactly what has changed in this pitch during this season. This pitch came in 4 miles an hour faster at 89.4, spun at 2322 RPMs, had only 26 inches of vertical break, but broke horizontally at 6 inches (three inches more than league average). For example, there are only four pitchers in baseball who have an average horizontal break on their cutter of 6 inches.