The Mets have designated left-hander Jose Castillo for assignment, per a club announcement. The move makes room for the addition of lefty Gregory Soto to the active roster. Soto was acquired from the Orioles on Friday.

Castillo, 29, debuted with the Padres all the way back in 2018. That rookie year saw him pitch to a 3.29 ERA with a 2.64 FIP in 38 1/3 innings of work while striking out opponents at a 34.7% clip. It was an impressive showing, but injuries and ineffectiveness limited Castillo to just three total outings in the majors over the next six seasons. He surrendered five runs on four walks while striking out three in two innings of work during those outings, though he posted decent numbers at the Triple-A level with a 4.32 ERA in 125 innings of work with a 29.1% strikeout rate during that time.

The lefty eventually resurfaced this year and has split his time between the Mets and Diamondbacks. His five outings in Arizona went quite poorly, as he surrendered eight runs on ten hits and three walks while striking out just three in 6 1/3 frames, but since joining the Mets back in May he’s looked much better with a 2.19 ERA and 2.76 FIP in 14 appearances. Castillo has already been designated for assignment and outrighted off New York’s roster once this season. He’ll now go through the waiver process again unless the Mets are able to work out a trade involving him prior to Thursday’s trade deadline. If he goes unclaimed on waivers once again, he’ll have the opportunity to either accept an outright assignment to the minor leagues from the Mets or elect free agency, at which point he would be free to sign with any of the league’s 30 clubs on a fresh contract.

Replacing Castillo on the roster is Soto who the Mets dealt a pair of prospects to Baltimore in order to acquire. The southpaw has a 3.96 ERA in 36 1/3 innings of work for the Orioles this year, with a 27.5% strikeout rate and a 3.28 FIP. A two time All-Star with the Tigers in 2021 and ’22, Soto was shipped to the Phillies prior to the 2023 season and has struggled during his time with Philadelphia and Baltimore since then, with a lackluster 4.53 ERA across the 2023 and ’24 seasons despite a tidy 3.63 FIP. The Mets will surely help that they can help him return to his prior All-Star caliber form so he can join the late-inning mix alongside closer Edwin Diaz, but even if Soto is little more than a league average middle relief arm for the club he’ll offer much-needed depth to a bullpen that has lost a half dozen relievers to the injured list already.