Going Deep: Joe Musgrove Could Be Better, If He So Chooses

A few weeks ago, I wrote an article about Tyler Beede. In it, I talked about how Beede could pretty feasibly be much better next year because of some changes he’s made, and other changes he could make. In the article, there was another pitcher who I don’t think is all that dissimilar to Beede, but I do think he’s better. That pitcher is Joe Musgrove.

I’ll get straight to it. I like them both because they have good enough fastballs, and three secondary pitches that make hitters swing and miss. If you didn’t read my Beede piece, then you’ll have missed this graphic, showing just how unique their ability to induce swinging strikes with multiple pitches is:

 

 

In a vacuum, this is awfully impressive. Musgrove is in the same boat as Gerrit Cole, Noah Syndergaard, and Zac Gallen here. And then there’s Beede. Of course, this isn’t an apples-to-apples comparison, because Cole’s ability to use a fastball as a swing and miss pitch is substantially more valuable than, say, a curveball that induces swings and misses. And it also leaves out pitchers who don’t have three qualifying pitches because they don’t necessarily need them. Regardless, as the graphic states, this is elite company. Given this, you’ll be quite confused by what I’m about to show you, if you aren’t already familiar.

Musgrove’s pitch usage and pitch type xwOBA, from 2018 to 2019:

This is a pretty common complaint with Musgrove. With the quality of his secondary pitches, why on earth is he using a fastball heavy, kitchen sink approach? The easy answer is Ray Searage, although I’m not sure that’s the whole answer. In any case, since taking over the reins as the Pirates’ pitching coach in 2010, Pirates starters rank third in the league in fastball usage (omitting cutter usage). While sinkers are becoming a dying breed, Searage’s pitchers have leaned into it, leading the league in sinker usage since 2010 at 19.7%. It’s unclear how much of this was Searage’s doing — he has denied imposing a pitch-to-contact approach on his pitchers — but the Pirates also fired GM Neil Huntington, so their entire philosophy will have theoretically been displaced by the time pitchers and catchers report in February.

Importantly, the Pirates hired pitching coach Oscar Marin to replace Searage. I’ll admit that I’m a huge sucker for coach-speak, and I get caught up in spring training and offseason anecdotes all the time. That aside, there’s a lot of reasons to like this hire. First, he’s 37. That’s not to say there’s necessarily a negative correlation between age and philosophical rigidities, but I’m not not saying that either. More so, his limited major league experience shows that the Pirates must like him a lot, and he’s theoretically unsullied by conventional wisdom or dogma. I’m a huge fan of aggressive hires like this. He spent time as the Mariners’ minor league pitching coordinator, and then as bullpen coach of the Rangers, and both of those organizations are quite savvy as it pertains to development and analytics. He’s been described as dialed into analytics, and he’s talked about maximizing his pitchers’ abilities. Until he gives me a reason to think otherwise, Marin sounds like a dream for Musgrove, as well as Keller and the rest of their pitching staff.

There’s already a fantastic foundation here. We know Musgrove has his trio of secondary pitches, but I love his other skills too. He’s got a Command+ of 110, which is is superior to Shane Bieber’s Command+, so then maybe it’s not a surprise that he’s one of the best strike-getters in the league. That’s not always good — Mike Leake just trails him, because this includes batted balls. However, if we eliminate the batted balls, we’re left with CSW. Even with the amount in which he throws his fastballs, Musgrove has a 28.8% CSW, which, while about league average, also tops pitchers like Sonny Gray, Mike Minor, and Zack Wheeler. Could be better, could be worse, but it’s clear we already have something to work with. And that’s to say nothing of Musgrove’s ability to further maximize his repertoire. Let’s take a look at what a new and improved Musgrove would look like.

If you look at his career percentage whiffs on his fastball, it looks like Musgrove has a solid fastball. Paired with his 82nd-percentile fastball spin rate, everything looks good. There are two issues there, though. First, if you only look at his 2018 and 2019 — the two years he’s essentially been a starter exclusively — you’ll find that his whiffs take a big hit. Second, his overall spin rate looks good, but his 59.4% active spin rate is putrid — it ranks in the third percentile. A low active spin rate means his fastball lacks perceived rise and gets more sink — it’s more sinker than four-seam fastball. So then it shouldn’t come as a surprise that Musgrove ranks in the 27th percentile in fastball CSW at 26.5%. I hadn’t seen this before making this soft comparison, but Musgrove and Beede are tied in fastball CSW from 2018 to 2019. Clearly, Musgrove should throw his fastball less (and Beede should too!).

That’s substantiated by this: In 2019, Musgrove ranked in the 88th percentile in breaking and offspeed pitch CSW at 34.9%. That’s tied with Patrick Corbin! So, as with my Dylan Bundy article, I propose we alter his pitch mix.

Here’s what I’m suggesting:

I wanted to be as realistic as possible, and so, by pitch type, these are pretty subtle changes. However, this would be a decrease from throwing 57.8% fastballs to 47.5%. I still wish he’d throw less, given his fastballs aren’t great, but these changes would already get him into unique territory as it pertains to not throwing very many fastballs. The thing is, even Corbin can’t afford to do this, because he’s got one absurdly good pitch (although his slider is technically two) and several middling pitches. Musgrove’s got three good pitches, and so while he doesn’t have one that draws whiffs to the extent that Corbin’s can, he can throw all three of these in the zone, which gives him flexibility.

Using my proposed pitch mix and his pitch type xwOBA from 2018 to 2019, we can calculate Musgrove’s theoretical xwOBA by multiplying his xwOBA values by his pitch percentages. Here is what Musgrove could look like in 2020:

We can do the same thing for his CSW, too, using his 2018 and 2019 numbers once again:

From 2018 to 2019, Musgrove put up a CSW of 28.8%, which is about league average. Here, we’ve managed to increase that to 30.3%, which is above league average! That would bump him from the 61st percentile to about the 77th percentile, which is about a Carlos Carrasco-esque level of performance. From Musgrove’s 2019 .305 xwOBA, which slots into the 71st percentile, his theoretical .287 xwOBA bumps him up into the 86th percentile, right above Lance Lynn.

I caution against taking this too seriously. Pitching is so, so incredibly complex, and it’s never as easy as taking numbers, changing them, and plugging them in to calculate a new CSW or xwOBA. Even if Musgrove takes on a new pitch mix that looks like what I’ve proposed, there’s bad luck, human nature, regression, reversion, and many other things that can take place. Pitching is an interconnected process, and yet this exercise gives us an idea of what Musgrove could be.

Musgrove, along with many other players, was traded for an ace in Gerrit Cole. Musgrove is not yet an ace, and with such an uninspiring fastball, it’s harder to envision him ever becoming one. Some players do it without a good fastball, but most do not. The Pirates haven’t let him pitch to his strengths, but it looks increasingly likely that that’s going to happen in 2020. He has some good pitches that he should throw more than his pitches that are not good. It’s as simple as that.

Graphic by Nick Kollauf (@Kollauf on Twitter)

Joe Musgrove photo by Frank Jansky/Icon Sportswire | Adapted by Zach Ennis (@zachennis on Twitter and Instagram)