Multiple Mets Starters' Jobs Could Be in Jeopardy as Kodai Senga Begins Rehab

His one-month rehab clock began on Friday night.

Here's what the latest on Kodai Senga means for the rest of the Mets' rotation. | D. Ross Cameron-Imagn Images

Veteran right-handed starter Kodai Senga began a rehab assignment with the Class-A St. Lucie Mets on Friday night, signaling the impending return of the Mets' highest-paid starting pitcher. Senga went down and was placed on the injured list in April with lumbar spine inflammation in his lower back, and has missed over a month of action already. He only made five starts with the Mets before hitting the injured list, allowing 20 earned runs in as many innings of work.

The Mets' starting pitching has been far from an issue of late, but their group is growing noticeably thin. Clay Holmes went down with a fracture in his leg that will keep him out into August, opening a permanent spot in the Mets' rotation. The likes of rookies Zach Thornton and Jonah Tong are names under consideration to see time in Holmes' spot, but the Mets have not given much of an indication as to who will get the start the next time through the rotation.

Tong has earned at least one more showing next week, but there is no clarity on what Thornton's immediate future holds. He was optioned to Syracuse to make room for reliever Jonathan Pintaro, but could see a quick return to the Mets' active roster as the cycle of arms continues between Queens and Syracuse.

We have made the following roster moves. pic.twitter.com/tnVMz3sGuH

— New York Mets (@Mets) May 23, 2026

A return from Senga could put a major wrench into the plans of both young starters and place more pressure on more established Mets arms. Senga has one month to return from the injured list, since his rehab window is open, meaning that we will see him back in Queens, barring any setbacks, before the end of June. If and when he returns, the Mets might have to make a few uncomfortable roster decisions. These arms, in particular, could be in a dangerous spot heading into the next month.

A return for Kodai Senga could leave multiple Mets starters without a job

A returning Senga is bad news for rookies such as Tong and Thornton, but could also lead to tough conversations around starters Christian Scott and David Peterson. Scott started the year in Triple-A Syracuse, but quickly rejoined the Major League team before the end of April once injuries began to pile up in Queens. Over five starts, he has posted a respectable 4.12 ERA, but has struggled with walks—he owns a 5.5 BB/9 and a 1.475 WHIP on the season.

Command was one of Scott's calling cards during his meteoric rise from college reliever to top-100 prospect starter, but he has struggled to find the strike zone since returning from Tommy John surgery. His lack of command has seriously shortened his outings so far, as he averages just four innings per start.

Similar to Scott, command has always been a major flaw in Peterson's game, as he's had a rollercoaster season. The Mets have begun using openers in front of Peterson, an effective role for reliever Huascar Brazobán so far, and it has helped limit some of his early-season struggles. The veteran lefty was horrendous to start the season, posting a 6.53 ERA in the first month of action.

David Peterson is another Mets starter who could lose his job to Kodai Senga. | Mark J. Rebilas-Imagn Images

His struggles led to the Mets deploying openers in front of him, and it has worked wonders: Peterson has allowed just five earned runs in 20 innings as a reliever behind an opener this year, compared to 22 earned runs in 28 1/3 innings as a starter. The Mets have found a way to make him effective again, but it still might not be enough to keep him in the Mets' long-term pitching plans. It should also be noted that Peterson is in the final season of his initial contract with the Mets and will hit the open market in November.

The Mets have made it very clear over the last three years that they will give Senga every chance to be an effective starter for them, and it could come at the expense of a few other Mets. He has typically required a sixth starter to give him adequate rest, which only makes this issue even more complicated for President of Baseball Operations David Stearns and his team.

Only one thing is certain as of right now: Senga's 30-day rehab window opened on Friday night in St. Lucie, and a decision on his future with the team is coming soon.