Pittsburgh Pirates: What 2021 Could Hold For Mitch Keller

Mitch Keller has had a strange career up to this point with the Pittsburgh Pirates. What could the 2021 season hold for the young right-hander?

Pittsburgh Pirates starting pitcher Mitch Keller probably has had one of the weirdest starts to a MLB career in recent history. Keller’s 2019 was extremely unlucky. His surface numbers hated him with a 7.13 ERA and 1.83 WHIP across 48 innings of work. However, he put up a healthy 28.6% strikeout rate and a 7% walk rate and 1.13 HR/9 leading to a 3.19 FIP. He also had a solid SIERA (3.78) and xFIP (3.47). Keller put up strong expected stats on Baseball Savant with a .389 xSLG, .308 xwOBA and 4.00 xERA.

Keller was victimized by bad defense and luck. Despite his hard hit rate and exit velocity, opponents managed an absurdly high .475 batting average on balls in play. It’s the highest BAbip mark in MLB history among starters with at least 40 innings pitched in a season.

Going into 2020, Keller looked like a prime breakout candidate. But Keller went from extremely unlucky to extremely lucky. He pitched just 21.2 innings in the COVID-19 shortened season, but also missed a few starts because of an injury. Keller put up a strong 2.91 ERA, but it was a very empty ERA. Keller walked more batters than he struck out with a 16/18 strikeout to walk ratio. To go with that, his HR/9 rose to 1.66. Keller’s FIP, xFIP and SIERA were all approaching seven. Keller somehow managed a .104 batting average on balls in play, a record low for any pitcher with at least 20 innings pitched and 93.8% left on base percentage. The league average left on base percentage was 72% in 2019 and 2020.

One of the last games of the season Keller pitched in perfectly summarizes his 2020 season. On September 25, 2020, Keller tossed 5.0 no-hit innings. He was pulled after the 5th inning because of his pitch count which was at 98. Despite throwing a no-hitter, Keller had allowed a run because he walked 8 batters. The one run scored on a ground ball double play with the bases loaded.

So what does this mean for Keller’s future? Keller is still young. 2021 will be his age-25 season. He also is still a talented pitcher. His fastball and curveball are considered 55 grade pitches and his slider is a 60 grade pitch on FanGraphs. FanGraphs might rank him change up as a 30-grade pitch, however, it’s been a continued work in progress. His three other pitches are very good. He also is considered to have good control with a 55 current command grade and 60 future grade.

In Keller’s defense, 2020 was not normal, obviously. The abrupt shutdown in March, three month layoff from baseball activities and sudden ramp-up for a 60-game MLB season did Keller no favors.

He hasn’t even pitched 75 innings yet either. Any stats from 2020 should be taken with a grain of salt for most players because no player got a decent amount of playing times. In 2019, the 60th game of the season for the Pittsburgh Pirates was in the first week of June. Under more normal circumstances, Keller could be the breakout candidate many fans were looking for after showing a decent amount of potential in 2019.