SF Giants: Could Mets RHP Michael Wacha Be 2021’s Kevin Gausman?

SF Giants fans know the team’s starting rotation needs to add talent this offseason. Many hope the team can emulate the success they found signing Kevin Gausman last offseason. Could the Mets Michael Wacha be that player?

As free-agency continues moving at the speed of molasses, SF Giants fans are trying to figure out who will be the newest member of the team’s rotation. Michael Wacha is far from the biggest name available, but the right-handed pitcher who spent the 2020 season with the New York Mets might actually be poised for a breakout 2021 campaign.

Much like Giants starter Kevin Gausman, Wacha was a first-round pick that quickly found success in the major leagues. However, he never reached the lofty expectations many placed on him. A series of injuries ultimately forced him back to square one. While Gausman never dealt with injury issues, his career followed a similar trajectory entering his breakout 2020 campaign.

Both Gausman and Wacha entered free-agency last offseason. Looking to rebuild their value, both signed one-year deals. While Gausman’s performance with the Giants earned him a qualifying offer this offseason, Wacha posted some ugly numbers with the Mets. However, a closer look at his performance presents an intriguing comparison.

Key: * denotes career-best

Wacha’s 6.62 ERA and 5.25 FIP come with a lot of sticker shock, but a massive spike in his home-run rate drives those numbers. Batted-ball data suggests he suffered a good amount of bad luck on balls in play, especially fly balls. xFIP, which treats home run-to-flyball ratio as out of a pitcher’s control, and xERA, which considers batted-ball data, both put his 2020 season on par with Gausman’s 2019.

His strikeout-rate of 23.7% was his highest career mark since his debut in 2013. His walk-rate of 4.5% was easily the lowest of his career as well, combining for a career-high K-BB%. When you take into account his massive .366 batting average on balls in play (BABIP) and low 68.4% left on-base percentage (LOB%), substantial positive regression seems very likely next season.

Of course, looking at general numbers alone in a 60-game season can be deceiving. Plenty of pitchers posted intriguing peripherals in 2020, but something substantial changed in Wacha’s repertoire to explain the growth. His changeup looked like an out pitch. The Giants believed in Gausman’s ability to build a repertoire around his split-finger, and Wacha seems to have the capabilities to do the same with his changeup.

Even in 2020, opponents batted .303 with a .508 slugging percentage against all pitches that were not Gausman’s split-finger. While that’s part of what limits Gausman’s ceiling going forward, his split is dominant enough to still be effective. Opposing hitters whiffed 45.7% of the time they swung at his split. In 2019, that pitch’s dominance was already present, generating misses on 40.8% of opposing swings.

Wacha’s changeup lacks the recent track-record of dominance that Gausman’s carried into 2020, but this season, it looked like a potential carrying pitch. According to Baseball Savant, Wacha’s changeup added 1.3 inches of average vertical movement and 2.2 inches of average horizontal movement and emerged as an elite offering. Opposing hitters managed just a .198 expected batting average against the pitch and whiffed 40.8% of the time, the same rate Gausman’s split generated swings-and-misses in 2019.

A key difference between Wacha and Gausman’s track-records is injuries. Even as Gausman struggled, he rarely, if ever, missed a start. Wacha has undergone surgeries and was placed on the injured list this season with shoulder inflammation. While he did return to finish the season, it’s an obvious cause for concern.

Still, gambling on a pitcher’s in the free-agent market is always a risky proposition. After finding success with Kevin Gausman last offseason, the SF Giants could look to do it once again. If they do, Mets free-agent righty Michael Wacha presented a lot of similarities to Gausman in 2019. That on-field upside could make it worth the risk.