Article: Which Richard Fitts Should We Expect Next Season?

[Davy Andrews]

Richard Fitts didn't just pitch better during his brief September call-up with the Red Sox than he had in Worcester. He pitched very differently.

Yesterday, we named Richard Fitts our ninth-ranked Red Sox prospect and Alex Mayes wrote up the right-hander’s 2024 season. Today, I’d like to accompany that piece with a deeper dive, because Fitts had some of the oddest splits you'll see. The splits weren’t between his stats against righties and lefties, but rather his stats in the minors and majors. It’s not just that Fitts pitched much better in Boston than in Worcester, though he definitely did. It's that his results made him look like a totally different kind of pitcher. After running a 4.17 ERA in Triple A, he ran a 1.74 ERA in Boston. What we're interested in, though, is ERA estimators.

Level	G	IP	HR	ERA	FIP	xFIP	DRA
AAA	24	116.2	19	4.17	4.86	4.66	4.98
MLB	4	20.2	0	1.74	3.31	5.51	5.47

Fitts ran a lower FIP with the Red Sox too, but it’s not quite that simple. FIP gives you a better estimate of how the pitcher performed by stripping out batted ball luck. In order to do that, it only looks at walks, strikeouts, and homers. Fitts allowed 19 homers over 24 appearances at Worcester, so we should probably expect him to give up the occasional homer. However, over his four starts with the Red Sox, he didn’t allow a single homer, and naturally, FIP loved that. On the other hand, more advanced estimators like DRA and xFIP were much less impressed. xFIP relies on Statcast’s expected metrics, and Statcast thought that Fitts deserved to give up 0.7 home runs over his four starts. After all, it's not like no one ever hit the ball hard against him.

That fraction of a home run was enough to completely tank his xFIP, sending it all the way up to 5.51. You might be wondering why getting credited with just one portion of a homer was enough to wreck his xFIP, and we'll answer that question in a moment. First, though, it's important to recognize that it wasn't just luck that kept Fitts from giving up homers in Boston. Fitts didn't give up homers because he did a great job at limiting hard contact. He had a 41.2% hard-hit rate and a 90.3-mph average exit velocity in Worcester. Among pitchers who faced at least 100 batters while Statcast was tracking the data, that hard-hit rate put him in the ninth percentile. In other words, triple-A batters hit him extremely hard. But when he got to Boston, those numbers somehow fell to 33.3% and 88.5 mph. Not only was Fitts better, but his hard-hit rate was one of the best in baseball! How was he able to do this against big-league competition when he couldn’t do it against minor leaguers?

Now let’s get back to xFIP, because there’s a specific reason that seven-tenths of a homer was enough to completely ruin it for Fitts. As I mentioned, FIP looks at walks, homers, and strikeouts. Fitts had a league-average walk rate, but he struck out just nine batters for an extremely low 10.6% strikeout rate. There were 656 pitchers who threw at least 10 big-league innings in 2024, and that mark ranked 648th. Because he didn’t strike anybody out, just one homer – just one fraction of a homer – was enough to throw the balance out of whack and completely change the way that the advanced ERA estimators viewed Fitts.

That brings us to our next split, because it’s not like Fitts is incapable of striking batters out. He ran a 22.6% strikeout rate in Worcester, and before that, he’d never run a strikeout rate below 25% in any of his previous minor-league stops. Fitts ran a 25.3 whiff rate in Worcester. That wasn’t great even for Triple A, but in Boston, it fell all the way to 15.2%. Fitts simply couldn’t miss big-league bats. What made it even stranger was that he did induce lots of chases. His excellent 32% chase was almost exactly the same as the one he ran in Worcester. Chases and whiffs usually go hand in hand, but in this case, Fitts simply couldn’t get batters to miss, even on pitches out of the strike zone.

So that’s where we are. In Triple A, Fitts racked up plenty of chases, whiffs, and strikeouts, but he allowed enough home runs and loud contact that his overall line wasn’t particularly impressive. Once he got to Boston, Fitts continued to get chases, but he lost the ability to miss bats. However, what he lost in strikeouts he made up for by inducing weak contact. In other words, his profile completely flipped. I don’t have any bright ideas about why this might have happened, and we’re talking about a tiny sample of just four starts. Still, I wanted to write about it because if you watched those four starts without diving into the numbers, you might have come away from the 2024 season thinking that Fitts was a master of contact suppression and that his game revolved around keeping hitters guessing rather than striking them out. That's probably not true. Fitts didn't change his pitch mix drastically when he got to Boston. He leads with his four-seam fastball, and nearly all of his pitches are rising as they approach home plate. Pitchers with arsenals like that tend to earn a lot of strikeouts up above the zone, but also tend to give up a lot of fly balls and home runs. Fitts is young and he's still learning. I don’t think we know what to expect from him just yet, but the version we of him we saw over four starts in September is probably not what we should expect going forward. It might even be backwards.

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