2025 stats: 67 IP, 55 G, 3.90 ERA / 3.70 FIP, 1.40 WHIP, 20.4 K%, 11.3 BB%, 0.5 fWAR
After a mini breakout in 2024, José Buttó looked like he might be a reliable dude in the Mets’ grand plan. He pitched
74 innings (the first 38 of which came as a starter) and was about as valuable (1.0 fWAR) as Luke Weaver and Josh Hader. His Statcast page looked exciting, too:
According to fellow SB Nation site Amazin’ Avenue, he’d pitched himself into Mets manager Carlos Mendoza’s “circle of trust” when it came to relief arms.
What a difference a year makes.
He was predicted to be in the mix for a late inning role, “right behind Edwin Díaz on the bullpen depth chart and […] alongside Reed Garrett and A.J. Minter,” but that didn’t wind up happening and his performance was down enough from 2024 to compel the Mets to seek an upgrade elsewhere. He was, essentially, a throw-in component of the Giants’ massive Tyler Rogers trade with the Mets at this year’s deadline. That was in part because Buttó is out of options but mainly because New York didn’t have the time to see if he could regain some of his lost form.
This is the trouble with relievers. They’re fungible and mostly unpredictable. Usually, we’d see a 27-year old with declining peripherals and chalk it up to a latent injury about to assert itself. If Blade Tidwell and Drew Gilbert were better than replacement-level players the next few years, the trade’s a win and Buttó an afterthought. Only, Buttó‘s been good enough across four seasons that he’s the type of arm you don’t necessarily through away because of a bad couple of months. And, to be clear, Buttó was pretty much awful over the final two months of the season. To the point that the Giants might simply non-tender him?
He hit the IL on the Fourth of July with an unspecified illness, however. Up to that point, he’d pitched 43.2 IP with a 2.47 ERA (3.39 FIP) for the Mets. After his activation on the 23rd, with both the Mets and Giants, he pitched 23.1 IP with a 6.56 ERA (4.29 FIP). That alone suggests an offseason of rest might go a long way towards righting the ship — depending on the nature of the illness, of course. Under the hood suggests that the declining peripherals could be explained by this illness, too.
And then there’s the matter of his peripherals being not all that decline-y.
2024: 26.9 K%, 12.9 BB% (bottom 3%), 94.2 mph 4FB, .319 xwOBACON (top 6%), 3.44 xERA, 88.7 avg exit velo
2025: 20.4 K%, 11.3 BB% (bottom 9%), 95.2 mph 4FB, .379 xwOBACON, 4.51 xERA, 90.1 avg exit velocity
The uptick in velocity could be explained by pitching all innings out of the bullpen instead of being a starter, which isn’t necessarily a point in favor of “everything’s going to be okay,” but an interesting couple of supporting items do point in that direction: (1) he had a career-best 48.1% groundball rate (41.5%, 42.2% previous two years), and the batting average on balls in play shot up from a two-year average of .231 to .309. A decision was made to switch up his pitch usage. Last year, he was a four-seam, sinker, changeup guy, and this season he was a four-seam, slider, sinker guy.
Buttó has the stuff to get swing and miss, but he at least for this season he wasn’t able to put hitters away with any consistency. This was a problem for the Giants as, according to FanGraphs, his leverage index in the orange and black (that is, the average pressure he saw coming into a game) was 1.32 (46th out of 131 relievers with a minimum of 20 IP from August 1st onward). His Win Probability Added was -0.08 (98th out 131). He was the worst Giant outside of Ryan Walker, whose -0.88 WPA in just 17.2 IP from August 1st to the end of the season was 15th worse (once you drop the threshold to a minimum of 10 relief innings).
Two of his top 5 highest leverage moments came with the Giants and those wound up being a blown win against the Cardinals on September 24th and the blown save he had against the Mets in his Giants debut.
Now, he still has five years of team control, which does matter in terms of roster construction. The Giants do have some flexibility there — only Matt Gage, J.T. Brubaker, and possibly Joey Lucchesi lack options — and having 3-4 relievers without them wouldn’t work against any sort of planning. At least in 2025, Buster Posey continued the tradition of acquiring relievers wih 95+ mph fastballs and 2,500+ rpm slider relievers. Unless there’s a philosophical change in the offseason, I don’t see Buttó being removed from the plan. He might not wind up being a 7th inning or greater guy, but as another multi-inning arm, his value is pretty clear.
The most excited Giants fans got about Buttó in 2025 was the trade package he was a part of, which means he’ll need to pitch his way back into the fans’ hearts and minds. That’s pretty much the life of a reliever, though.
