Mets' David Peterson using slider to produce more effective results
Mets starting pitcher David Peterson delivers during the third inning of a baseball game against the Dodgers in Los Angeles on April 13, 2026. Credit: AP/Kyusung Gong
DENVER – If you paid attention, David Peterson has been talking about the problem all along.
It was after his third start of the season, a clunker on April 8, that he pushed back when he was told that he wasn’t executing his fastball inside to righthanded hitters.
“I don’t think I’ve had a problem executing that pitch,” he said then. “I don’t think we’ve gone there enough. I think we’ve relied on the sinker and changeup too much and allowed hitters to kind of sit over the plate.”
A month later, after his excellent four innings in relief against the Rockies in the Mets' 4-2 win Monday, he added another layer. In this game, he significantly increased his slider usage – a pitch that, like the fastball, moves glove-side, which, for the lefty, means inside to righties.
“I think it’s been my best off-speed pitch,” he said. “I went back and looked at some of the stuff and there was some usage stuff that I wasn’t necessarily happy with – one being that in the last month, I was using the curveball more than the slider when the slider is one of, if not my best pitch, and the curveball overall is on the bottom of the list. Switching that today and kind of being able to attack with the fastball and the slider off of it, I felt like I gave us a really good chance.”
It’s easy to say that Peterson, who worked as the bulk guy behind Huascar Brazoban and Austin Warren Monday, simply does better when he doesn’t start games. The ERA will certainly bear that out – 8.10 in five starts, as opposed to 2.45 when he comes out of the bullpen. But there’s clearly more to this story, and it’s possible that if you listen to the guy in the very middle of it, there’s an answer to be found, and it comes from usage and pitch sequencing.
For his part, manager Carlos Mendoza also doesn’t think that the key to unlocking Peterson relies wholly on having someone pitch before him.
“It’s easy because of three [relief] outings now where he’s been really, really good, but I keep saying, he’s a starter,” he said. “He’s really good when he’s at his best. We saw today. I think the key is attacking the strike zone. He pounded the strike zone today with everything. That slider was good…The four-seam, the slider was his pitch. He’s too good of a pitcher and I know he’s going to continue to help us.”
Looking into the numbers, there are a few factors at play.
For one thing, Peterson is right. Though he didn’t come out and express frustration, it’s clear he hasn’t been completely satisfied with previous game plans – especially when it comes to his slider usage.
His sinker is his most-used pitch – he throws it 31.7% of the time – but it’s also one of his weaker offerings, worth -1.7 runs per 100 sinkers thrown. His changeup and curve have overall been even worse, but his fastball is middling, and likely good enough to set up a slider that tracks as among one of the best pitches in baseball. According to Baseball Savant, the pitch has a 4-run value so far this season, on par with those thrown by Jacob deGrom and Tanner Scott.
Monday, he allowed two runs and three hits with no walks and six strikeouts over four innings. His slider made up 36.2% of his pitches, and his fastball was his second most-used pitch (26.1%). It’s the first time this year he's relied that heavily on the offspeed pitch, which he had been throwing 20.8% of the time; he instead opted for his sinker more often than any offering.
“Today felt really good,” he said Monday. “I felt like I was attacking right away and I felt like we were in 0-1, 0-2 counts a lot…I felt like Luis [Torrens] and I were on the same page and kind of what I was thinking, he was throwing down. [It was] a good day at work overall.”
That, too, might be a factor. Peterson has done better with Torrens behind the plate over Francisco Alvarez – a 7.42 ERA this year with Alvarez (26 2/3 innings) compared to a 2.35 ERA (7 2/3 innings) with Torrens. It’s a small sample size, but that’s also been true throughout his career, though the margins are smaller. He has a 4.53 career ERA with Alvarez behind the plate as opposed to a 3.20 ERA with Torrens.
Either way, it should give fans some solace. The bottom half of the Mets rotation has been in shambles, but getting Peterson right is a potent tool. This was, after all, the starter who carried them for the first half of last season, even making his first All-Star appearance.
“He’s a really good pitcher,” Mendoza said. “We’re counting on him. We’ve got to get him going.”
It’s a process, sure. But maybe the keys to that are already in the Mets’ hands.
Laura Albanese is the Mets beat writer for Newsday. She's been covering MLB since 2014 after starting at Newsday as an intern seven years earlier.
