The Mets have been on the hunt for rotation help this winter, and that search has led them to a veteran lefty.

The Mets signed veteran left-hander Sean Manaea to a two-year contract with a player opt-out after the 2024 season, the club announced on Friday. The deal is worth $28 million, a source told MLB.com's Mark Feinsand. The move continues reshaping New York’s rotation under new president of baseball operations David Stearns.

In a corresponding move, infielder Diego Castillo was designated for assignment.

Manaea, who turns 32 on Feb. 1, is an eight-year veteran who went 7-6 with a 4.44 ERA across 117 2/3 innings last season for the Giants. He bounced between the rotation and bullpen most of the year but finished strong, pitching to a 2.25 ERA in four September starts.

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In those appearances, Manaea flashed the promise that made him a reliable mid-rotation starter as recently as 2021, when he tied for the American League lead with 32 starts and recorded a 3.91 ERA with the A’s. But he endured a career-worst year with the Padres the following season and initially struggled in San Francisco, before adding a sweeper to his pitch mix midseason and finding success, first in middle relief and then back in the rotation. He finished 2023 with the best strikeout-per-nine (9.8) rate of his career.

All told, Manaea owns a career 65-56 record and a 4.10 ERA in 1,002 2/3 innings across eight seasons for the A’s, Padres and Giants. His career ERA+ is exactly league average (100) over 196 career appearances (166 starts).

In New York, Manaea would seem to slot into the back end of a rotation that has been very much transformed in the last few months, first by Billy Eppler and now by Stearns. After Eppler traded Max Scherzer and Justin Verlander at last year’s Trade Deadline, Kodai Senga and José Quintana profile as the group’s only full-time holdovers from 2023, with Tylor Megill, José Butto and Joey Lucchesi providing depth.

The addition of Manaea comes after Stearns signed bounceback candidate Luis Severino to a one-year contract and traded for right-hander Adrian Houser in a deal with Milwaukee in December.