There’s Hope for a Martin Perez Bounce Back
Image courtesy of © Jennifer Buchanan-USA TODAY SportsBefore his awful 2018 season, Perez was a reliable backend of the rotation starter for the Texas Rangers. In both 2016 and 2017, Perez put up consecutive 2.1 fWAR seasons after combining for a 4.60 ERA across 383 2/3 innings. While these numbers don’t exactly jump off the map, anytime you can get those numbers out of your fifth starter in the rotation you are in a better situation than most rotations, especially when compared to those in recent Twins history.
Even though Perez had a 6.22 ERA in 2018, many advanced statistics pointed to him being nearly the same pitcher as he was in his two prior seasons. While Perez’s FIP wasn’t that appealing at 5.72, his xFIP was far lower at 4.98. For those that aren’t familiar with the difference between FIP and xFIP, xFIP uses the same baseline as FIP except it also accounts for a pitcher’s HR/FB rate. In 2018, Perez had a HR/FB rate of 18.2%, which far exceeded his career average of 11.7%. It can be expected that for this number to return to his norms in 2019, and thus will have a large impact on Perez’s run prevention.
Additionally, many of the Statcast metrics also tell the story of Perez being nearly the same pitcher in 2018 that he was in 2016 & 2017. When a pitcher has a down season it often coincides with a decrease in pitch velocity. This can often be worrisome to MLB teams as it can be an indicator that the pitcher has fallen off physically. However, when looking at Martin Perez, that doesn’t seem to have been the case, as is evident by the chart seen below.
Another great way to use Statcast data to help predict a player’s future performance is by looking at their expected stats. When looking into these metrics, it yet again points to the fact that Perez was actually a much better pitcher in 2018 than his 6.22 ERA implies. Last season, Perez had a batting average allowed of .329, but his expected AVG (xAVG) allowed was just .287. This 42-point drop from actual batting average to his xAVG was the largest drop of any pitcher who faced at least 350 batters in 2018. When looking at a far more advanced stat like wOBA, we see the same thing. Last year, Perez had an actual wOBA of .390, but his xwOBA was 37-points lower at .353. This was the 4th largest drop off among the same 166 pitchers who faced at least 350 batters last season.
One thing that has kept Perez from ever becoming a top, or even middle, of the rotation starter is his well below average strikeout numbers. For his career, Perez has struck out a mere 13.9% of opposing batters. Of the 148 pitchers who have thrown at least 500 innings since Perez came into the league in 2012, Perez’s strikeout rate ranks 144th. Despite this, Perez has still been a serviceable starter for the majority of his career. In 2018, Perez’s strikeout rate checked in at 13.1%, barely below his career average.
At the end of the day, Martin Perez isn’t going to be that breakthrough signing that will put the Twins over the top. However, I think it is fair to assume that the front office had a plan in mind when signing Perez, and he could very well wind up serving a much bigger role on the 2019 Minnesota Twins than just adding depth to the starting rotation.
- nclahammer and caninatl04 like this