Nobody thought that Matt Chapman would repeat his transcendent 2024 season (5.4 fWAR), but he’s had a somewhat anonymous start to his 2025 for the San Francisco Giants. Oh sure, there have been highlights on both sides of the ball, but .217/.338/.411 doesn’t sit quite right. A quick scan of his Statcast data suggests a reason: he’s been tremendously awful against the four-seam fastball this season. Does that mean he’s going to be just good and not great? Not necessarily.
I’ll admit that his .217 average is what continues to stick out to me. When I think of Matt Chapman, I think of a .230/.240 hitter — not all that good, of course, but the on base and power usually make up for it. Right now, he’s got a .750 OPS. Also pretty soft for what he normally is. Given that we’re just a quarter into the season, I’d say that gives him room to grow and that’s an exciting prospect as the weather gets warmer and the Wild Card race tightens. Is there enough information in the data to suggest that rise is coming?
No need to hold your breath. The answer is: yes. Run Value is the main stat I’m looking at in this situation and that is a purely contextual stat. As Baseball Savant (Statcast) defines it:
Run Value Definition: the run impact of an event based on the runners on base, outs, ball and strike count.
Chapman’s -4 Run Value against the 4-seam fastball is 17th-worst in MLB (minimum 50 plate appearances), placing him among a crop of players you’d expect to be doing a lot better against a fundamental baseball pitch. Jung Hoo Lee is outpacing him with a -6 and Anthony Santander is right there with Lee. Tied with Chapman? Mike Yastrzemski.
Statcast has existed for all of Chapman’s career, so we can look at the whole thing and see what’s going on. He hasn’t been this bad against the four-seamer since his rookie season of 2017 (-4 Run Value). Is this a sign that he’s simply nearing the end of his career? That he’s slowing down? I don’t think so.
I think we’re dealing with a slow-ish start to his 2025 in one specific area. While it’s true that his bat speed is down year over year by about 1.5 mph and closer to where it was for his disappointing 2023, the quality of his contact is such that Statcast believes he should be a bit better overall. His actual wOBA is .335 (league average: .314). His expected wOBA is .362. So, the thunder is still in the bat.
This is where it gets tricky, though. His numbers against four-seam fastballs with 95+ mph velocity are bad, generating a wOBA of .214. That does suggest an insurmountable problem, as it simply becomes harder to catch up with the heat. But! The Giants’ “leaderboard” against velocity offers hope:
There you see Mike Yastrzemski with above league average wOBA against velocity when earlier you saw that he had negative run value against the pitch. This means that it’s all a matter of context. Chapman’s struggles against the four seamer (and cutter) could simply be a matter of timing or result of sequencing. Teams have pitched him differently in 2025:
2025 breakdown: 61.1% (+2.4%) fastballs, 28.1% (-4.4%) breaking, 10.8% offspeed (+2%)
2024 breakdown: 58.7% fastballs, 32.5% breaking balls, 8.8% offspeed
Going back to last season, Chapman’s wOBA against 95+ was just .298, so, in terms of room for improvement, there is perhaps not quite as much as I would’ve expected when doing the analysis, but I mean, come on, how many four-seam flamethrowers is he going to face the rest of the season?
::handed note::
Oh, there are about 130 pitchers who average 95+ with their four-seamer? Okay, then.
(Nervous laugh)
No, seriously, there’s not a reason for panic. It’s very hard to hit 95+ consistently, and Chapman’s career reflects that:
So a great player having a good season is no reason to worry or wonder and should the rest of the Giants’ lineup become harder to pitch to Matt Chapman might find it easier to hit.
