Despite the fact that he is likely the fifth option coming out of the bullpen, this feels like a big season for Jonathan Loaisiga. He made some strides on the mound last year and his pitch mix–a fast, high-spin fastball and a whiff-inducing curveball–signals that he could be a great reliever. How can he take that next step?
Since I’ve been writing about and analyzing baseball, there are three things (aside from striking batters out) that pitchers ought to do to be successful: avoid walks, limit home runs, and get grounders. In 2020, Loaisiga did all of those things well, even in a short sample.
He posted a career low for walk rate (2.74 BB/9) and percentage (7.0%). His groundball rate at 50.8% was also a career high and a big improvement from 2019 (40%). He’s 1.17 HR/9 wasn’t his lowest (2018’s 1.07), but his HR/FB% of 17.6 was his lowest, a continuation of a downward trend: 20% in ’18, 19.4% in ’19, and then 17.6 in ’20. Those homer numbers aren’t great–especially for a reliever–but two of them came in his first two games of the season. After that, he let up only one homer the rest of the year.
All this led to career bests in ERA and FIP for Loaisiga (and, hence, ERA- and FIP-), so to ‘improve’ in 2021, it seems that all he needs to do is continue this trend of lowering walks and homers and keeping up the grounders. Regardless of just about anything else, that seems a recipe for continued success. However, one thing could tick back up: his whiff rate.
We can infer that the drop in whiff rate comes along with the higher groundball rate, which isn’t necessarily a bad thing. But, I want to focus on whiffs in a specific part of the zone where grounders really aren’t going to be an issue. First, let’s take a look at 2020.
And now 2019:
Pay particular attention to the zones up high, both in and out of the strike zone. Those are places Loaisiga should be getting lots of fastball whiffs for strikeouts, not weak contact for grounders.
If he can figure out the best of both worlds–grounders at the bottom of the zone and whiffs at the top–he’ll be a great reliever. I’m a big believer in Loaisiga and think he can do it and take that next step forward.