NEW YORK -- The 2023 version of Kodai Senga would have been a Game 1 playoff starter. Even last year, when Senga made just one regular season start due to injuries to his left calf and right shoulder capsule, the Mets deemed him worthy of bringing back as a surprise starter for the National League Division Series.
But in 2025, after a month and a half of continued struggles, Senga's spot in a Mets postseason rotation now appears to be in question.
Senga, who allowed five earned runs in 4 2/3 innings in New York's 5-1 loss to the Marlins on Sunday at Citi Field, has a 5.90 ERA in nine starts since returning from the injured list on July 11. Since the All-Star break, his ERA is 6.56.
"We've got to get him right, obviously," manager Carlos Mendoza said. "I'm sure we're gonna have some discussion about what's next for him. But our job is to get him right. But it's been a struggle. ... And again, we'll see what's next for him."
There is only a month left of the regular season for the Mets to fix Senga, who is an ace-caliber pitcher when he is at his best.
"I'm working my tail off to get back to that," Senga said through interpreter Hiro Fujiwara. "And it's as simple as: If I'm able to do it, we're in the postseason and I'm pitching out there. And if I'm not able to, then there's no spot for me to pitch."
Senga's struggles have coincided with a prolonged difficult summer stretch for New York. Entering September, with 25 games remaining, the Mets are 6 1/2 games behind the Phillies in the NL East, although they still hold a four-game lead over the Reds for the third and final NL Wild Card spot.
The Mets finished August with an 11-17 record, including dropping three of four games to the Marlins to end the month following what had seemed like an invigorating sweep of the Phillies earlier this week.
"It's a combination of a lot of different things, but it starts on the mound," Mendoza said. "Our starting rotation, we got some quality starts against the Phillies, and we didn't get many of them against [the Marlins]. We're going to continue to try to put the best guys out there, but understanding that we've [only] got a few games here ahead of us. We need to find that consistency."
Senga started the 2025 season 7-3 with a 1.47 ERA and 70 strikeouts in his first 13 starts, before a right hamstring strain landed him on the IL. Since then, he has been unable to return to form.
"To be honest, there's definitely some frustration," Senga said. "I've never experienced something like this for this extended period of time. There's some confusion -- why am I not able to perform? But at the same time, when I'm able to prepare well and when I'm able to do what I'm capable of out there, I know that I'm able to put up a good performance."
Senga, who is notoriously meticulous about his mechanics, has felt out of sync, especially with his lower half. After his previous start against the Phillies, he expressed that he was not generating the same power behind his pitches that he was used to.
Senga and Mets pitching coach Jeremy Hefner had a long meeting after that start to try to pinpoint how they could get things right. But it has not worked yet. Senga hasn't been able to execute his pitches consistently.
"There are some parts of my body that aren't moving the way I want them to, but at the same time, I'm out there and I'm competing," Senga said. "So it's a fine line, and it's tough for me because I'm out there, but I'm not able to perform."
Mendoza said after Sunday's loss to the Marlins that Senga has been throwing too many non-competitive pitches out of the zone, where hitters can tell it's a ball right out of his hand. Then, when he gets back in the zone, he's getting hit harder than usual.
"We've been trying to fix him for quite a bit now," Mendoza said. "Whether it's the mechanics [or something else] -- he says he feels fine physically -- but we're not seeing results. He's having a hard time competing in the strike zone. I know Hef and the pitching department are looking deep into a lot of different things here. They're trying to help him and get some feedback from him. But again, we haven't been able to get there."
One inning, Mendoza said, Senga will look like vintage Senga -- his fastball will have life, his forkball will drop off the table. The next, he'll start hanging his pitches and give up damage. The inconsistency has been the hardest problem for Senga and the Mets to solve.
"It's hard to describe," Mendoza said. "And that's what we're seeing from him. We've got to find a way to help him."