Sean Manaea's Improvement Could Be Huge for Mets' Rotation

Sean Manaea looked sharp in his longest appearance of the season on Monday. The Mets could use more of that from him going forward.

Sean Manaea allowed one run in five innings for the Mets in Seattle on Monday night. | Joe Nicholson-Imagn Images

One of the biggest keys to turning around the Mets' season is finding more stability in the back of their rotation. While Freddy Peralta, Nolan McLean and Christian Scott have been a solid top three, finding the answers for the final two rotation spots has been a challenging process for Carlos Mendoza.

With David Peterson losing a spot and going to the bullpen, Sean Manaea got his first crack at a start-adjacent spot in Seattle on Monday night. The Mets went to the bullpen model, using Austin Warren to serve as the opener, before Manaea entered and pitched very well behind him.

5 splendid innings as the bulk reliever for Sean Manaea pic.twitter.com/zty4Grzfzh

— SNY Mets (@SNY_Mets) June 2, 2026

The Mets saw the best Manaea has had to offer this season as he limited a strong Mariners offense to just one hit, a solo homer to Colt Emerson, in his five innings of work. Manaea walked one and struck out four, crediting improvement with his sweeper as a key to his success after the game.

"Throwing it hard and selling it has been really key," Manaea said via SNY TV. "The strikeout to (Luke) Raley, that's probably the best sweeper I've thrown all year."

Things went so well for the Mets that fans were actually upset that Manaea was pulled after the sixth inning. Part of this was results-oriented, as Brooks Raley failed to execute on a 3-2 pitch that Josh Naylor crushed for a game-tying homer, but Mendoza indicated after the game that Manaea was starting to see a bit of a velocity dip after his longest outing of the season.

How Sean Manaea can help solve the Mets' rotation issues

While the 63 pitches Manaea threw are not his season-high (74 vs. Giants on April 2), the five innings are the deepest Manaea has worked into a game this season. The Mets were unsure what to do with Manaea after his velocity was down in spring training, leading to some awkward bullpen construction, but it appears they have figured out how to get more out of him in a semi-starting role.

Sean Manaea's five-inning performance against the Mariners could be a sign of better things to come. | Sam Navarro-Imagn Images

President of Baseball Operations David Stearns has wanted to give Manaea a chance after choosing to give him a three-year, $75 million contract following his breakthrough performance at the end of 2024. Manaea was undoubtedly the Mets' ace down the stretch that year, but injuries wrecked his 2025 campaign, leaving his future with the team a bit murky.

Perhaps a return to a more defined role will help the Mets get more out of Manaea, who was undoubtedly thrown off by his irregular usage early in the season. Even if the Mets choose to use openers for him, the team could significantly benefit if Manaea can routinely get deep into games again going forward.

The next time Manaea's rotation spot would come up should be on Sunday in San Diego. The Mets were noncommittal about whether Manaea would actually start or work behind an opener again, but he has been trending in the right direction for a while.

Manaea has lowered his ERA by nearly a run and a half from the end of April, when it sat at 6.55, to his current 5.08 mark. If the Mets can find a way to utilize Manaea as a fourth starter, it could make Mendoza's life a lot easier as he figures out how to manage his bullpen on a daily basis.