The Mariners announced that they have claimed left-hander José Castillo off waivers from the Mets. The latter club designated him for assignment a few days ago. To open a 40-man roster spot, fellow lefty Joe Jacques has been designated for assignment. Castillo is out of options, so the M’s will need to make a corresponding active roster move once he reports to the team. Ryan Divish of The Seattle Times reported the claim prior to the official announcement.
Castillo, 29, has logged 21 2/3 innings this year between the Diamondbacks and Mets. He has allowed 4.98 earned runs per nine but with better underlying metrics. His 21% strikeout rate and 8.6% walk rate are both close to average, while his 52.9% ground ball rate is quite strong.
That performance hasn’t been enough to keep him in the majors for an extended stretch. Since he is out of options, he has been designated for assignment multiple times this year. Arizona gave him his first DFA of the season in May and then flipped him to the Mets for cash. Since then, the Mets have given him the DFA treatment three times. The first two resulted in him clearing waivers and sticking with the Mets, later getting selected back to the roster. Around the transactions, he also tossed 16 Triple-A innings with a 1.69 ERA, 35.9% strikeout rate, 9.4% walk rate and 50% ground ball rate.
On this third Mets DFA, the Mariners have swooped in to grab him. They already have three lefties in their bullpen, with Gabe Speier, Caleb Ferguson and Tayler Saucedo back there, but adding Castillo will give them even more balance in their relief corps. He has between four and five years of big league service time, so they can retain him for 2026 via arbitration if he still has a roster spot at season’s end.
Jacques, 30, signed a minor league deal with the Dodgers in the offseason. He was traded to the Mariners in early July. The M’s added him to their 40-man roster and then immediately optioned him to Triple-A. It’s likely that his deal with the Dodgers had some sort of opt-out or upward mobility clause. The Dodgers evidently weren’t willing to give him a 40-man spot but the M’s were.
In the minors this year, he has posted poor surface-level results with better underlying numbers. He has thrown 47 innings in the hitter-friendly Pacific Coast League with a 6.51 ERA. His 23.6% strikeout rate and 9.8% walk rate are close to par while his 59.7% ground ball rate has been quite good. He has seemingly been undone by a .393 batting average on balls in play and 57.7% strand rate, which are both on the unlucky side. His 4.61 FIP this year is far more optimistic than his ERA.
Despite the positive indicators, the M’s are moving on. Jacques is in his final option year and will therefore be out of options going into 2026. That would have made it harder for them to roster him going forward, so they are cutting him loose now.
Since the trade deadline has passed, he’ll be on waivers in the coming days. It some team believes he can post better numbers going forward, perhaps away from the PCL, then they could put in a claim. He can still be stashed in the minors for the rest of this year. He has less than a year of service time and theoretically has years of control, though as mentioned, he’ll be out of options next year. He has 29 2/3 major league innings with a 5.46 ERA, 15.9% strikeout rate, 8% walk rate and 61.9% ground ball rate.
Photo courtesy of Vincent Carchietta, Imagn Images