One Big Question: Will Josh Osich switch up his arsenal again?

Welcome to Over the Monster’s One Big Question series. For those unfamiliar, this is something of a season roster preview where over the next 40(ish) (week)days we’ll be taking a look at each player on the 40-man roster prior to the season. If changes are made to the roster between now and Opening Day, we’ll cover the newly added players. Rather than previewing what to expect in a general sense, the goal of this series is to find one singular question — sometimes specific, other times more general — for each player heading into the coming season. We’ll go alphabetically one by one straight down the roster, and you can catch up with the series here. Today, we cover Josh Osich.

The Question: Will Josh Osich stick with his 2019 approach?

Whenever the Chaim Bloom era ends, whether it be in a handful of years or a decade or, in some dystopian future with immortality, misleadingly helpful technology and a constant grappling of “have we gone too far?”, a century, we are going to mark the beginning of his tenure with the Mookie Betts trade. It will forever be remembered as the first transaction with him in charge, for obvious reasons. History doesn’t remember the minor moves. They remember the blockbusters, for better or for worse.

That wasn’t really his first change to the Red Sox roster, though. The real first transaction in the Chaim Bloom era (not counting players declaring free agency, obviously) was claiming Josh Osich off waivers from the White Sox. That obviously wasn’t a needle-mover, but keep that knowledge in your back pocket to win a bet in a very sad dive bar in Somerville in 2050, provided we’re not underwater by then.

Anyway, while this move wasn’t exciting it did sort of set up an offseason that, aside from the aforementioned blockbuster, has been filled with these minor additions for the pitching staff at the back of the 40-man roster. It’s kind of easy to forget about Osich simply because he was picked up so long ago — he was officially claimed on Halloween — but there’s an argument for him likely being the best of the group.

The lefty, who will be 31 for almost the entire 2020 season, has been in the majors with a full-time role almost totally since 2015, though he was sent down for some time in 2018. He spent most of that time with the Giants, serving mostly as a straight-up LOOGY and, honestly, never really pitching well. His best ERA in his three full seasons with San Francisco was 4.71. Remember, the Giants play in probably the best park in baseball for pitchers. Osich then moved on to the White Sox last year, throwing more innings than appearances for the first time in his career and pitching to a 4.66 ERA in the worst pitchers park (and in the American League) in his career while also putting up his best peripherals ever. The numbers were still far from standout (there’s a reason he was on waivers to begin with, ya know?) but he had a legitimate step forward in a new organization.

Even with some positive spin, Osich has been a below-average reliever with an average ceiling, which doesn’t exactly spell excitement. However, I find him endlessly fascinating because he is just constantly changing up his approach and repertoire in a way I’m not sure I’ve seen before. When he first came up — and all of this will be according to Baseball Savant — he threw four pitches at least ten percent of the time with his cutter and four-seamer being about even at the top. The next year he still used four pitches, but his sinker jumped way out in front, being used more than half the time. Then the next year, he became a two-pitch guy with a fastball and a slider, though his cutter was just outside ten percent. The next year was injury shortened, but in his 12 innings he was a fastball/changeup guy.

Last year was another major shift, and it was arguably his most interesting to date. In 2019, Osich leaned on neither his four-seam fastball nor his two-seam (sinker), instead using his cutter at a way higher rate than ever before. Just about 67 percent, to be exact. Along with that his slider and his four-seam also came in above ten percent, though neither got all that high over that mark. He has a track record of changing things up every single year, but I think this year he might be better off with a tweak rather than an overhaul.

The cutter was obviously the star of the show for him in 2019, and it got some pretty good results. Again, according to Baseball Savant, the pitch generated a whiff rate of about 27 percent with an expected wOBA of .308 and an actual wOBA of .313. He also did a fantastic job of commanding the pitch, regularly pounding the lower corner of the zone on his glove side.

I mentioned above that Osich had his best peripherals of his career last year, and a big part of that was the walks. In his two true full seasons in the majors before that, 2016 and 2017, he had walk rates of 4.6 per nine innings and 5.7 per nine. That is not going to cut it, especially because he doesn’t miss bats at anything really close to an elite rate. To have success, he needs to limit free passes, and he did that to the tune of two walks per nine last year. It wasn’t because he hit the zone any more than usual, though. Instead, he got more chases than ever before on pitches out of the zone. Looking at the zone plots and comparing it to 2017 (remember, he barely pitched in the majors in 2018), a big chunk of those chases came at the bottom of the zone, where he was throwing all of those cutters.

It wasn’t all good for Osich, though, or even for his cutter specifically. He did great in improving his walks, and he posted a solid strikeout rate too, but he was killed by home runs. Obviously everyone was killed by home runs last year, but Osich allowed 15 in just 67 ²⁄₃ innings, or two every nine innings. Ten of those came off the cutter, while four came off the four-seam and one off the sinker. One of the side effects of this latest repertoire change was a career-low ground ball rate, which came back to bite him with the juiced balls.

It also has to be noted that, although he threw more innings than appearances and got a bit away from the specialist role, he was still much, much better against lefties. That even applies to the cutter. The numbers I mentioned above on the pitch were good, but it was essentially all because of what he did against lefties. Righties whiffed 21 percent of the time against his cutter with a .377 expected wOBA and a .431 actual wOBA. Overall, he allowed a .229 wOBA to lefties compared to a .370 mark against righties. Baseball-Reference has a stat called tOPS+ that measures a player within splits, and by that metric only 13 pitchers were worse than Osich against righties compared to their performance against lefties. That is among 576 pitchers who recorded at least 30 outs against righties.

So, what does Osich do from here? Well, judging from history he’s probably going to make a pretty major change. He talked to FanGraphs shortly after being claimed by the Red Sox, and when asked about his constant repertoire changes he said, “If the scouting report is the same every year, they know what you’re going to be throwing.” Hard to argue with that! However, I would argue that his cutter was good enough, particularly against lefties, that he should keep throwing that a bunch. I would probably throw it less against righties and try more sliders and sinkers (both of which were good against righties last year, albeit in small samples).

Whatever he does, he’ll have to be good against everyone with the new three batter rule, but more than anything I’m just really interested to see how big of a change he makes. I’ll be keeping an eye out this spring for any hints.