Luis Castillo allows five runs in White Sox debut

Castillo is having the worst season of his professional career with a 5.06 ERA and 3-9 record over 20 appearances — 17 starts — and 99 1/3 innings. The 33-year-old right-hander has been much more effective in the past, however, and has pitched better after a dreadful start to his 2026 campaign. Still, this is not the Castillo of old, and he’s much closer to a streamer than someone fantasy managers need to have in their lineup. It’s fair to take a wait-and-see approach before believing in a rebound.

In exchange for Castillo, the Mariners will acquire right-handed reliever Seranthony Dominguez, outfielder Nolan Jones, and catcher/outfield prospect Boston Smith. The Whit Sox will also take on all of Castillo’s contract, which pays him 22.75 million the next two years with an option for 2028. The Mariners have long been rumored to explore trading a starting pitcher with Emerson Hancock and George Kirby’s name bandied about, but it’s Castillo who will be heading to Chicago. The right-hander is not the same hurler he was a few years ago when he was among the very best in the sport, but he’s a solid mid-rotation option for a team that has played well above expectations with an excellent chance of reaching October. He’s more streamer than fantasy stalwart, but perhaps the change of scenery helps Castillo find the form of the previous campaigns.

Passan adds that the sense is that Kirby is available and could be moved prior to Monday’s deadline. He also notes that Seattle has been listening to offer for Emerson Hancock and Luis Castillo. The Mariners have top prospect Kade Anderson knocking on the door of the majors and figure to move at least one, if not more, of their current rotation members. Kirby would net the largest return in any potential trade package, despite holding a pedestrian 3.98 ERA across 120 innings this season.

It’s fair to wonder whether Seattle will wait until mid-August to promote Anderson since that would allow him to remain rookie-eligible for next season. There will be a rotation spot open one they move on from either Emerson Hancock or Luis Castillo ahead of next week’s trade deadline. There’s a chance that both of them are on the move. Anderson has checked every metaphorical box during his professional debut with a microscopic 1.20 ERA and 119/12 K/BB ratio across 82 1/3 innings over 16 starts for Double-A Arkansas. Needless to say, Anderson should be stashed in all fantasy formats. His time is coming.

Castillo gave up a leadoff homer to Shohei Ohtani in the bottom of the first inning. He then loaded the bases with no outs in the third, but came out of it with just one more run allowed on a groundout. The Dodgers would add two more runs in the fourth, followed by a solo homer by Max Muncy in the fifth. Castillo’s day would be done after five frames, giving up 11 hits and issuing two walks while collecting just two strikeouts. The 33-year-old right-hander will take a 5.06 ERA, 1.39 WHIP, and an 86/32 K/BB ratio across 99 2/3 innings into a start against the Tigers in Seattle next Tuesday.

Castillo served up a leadoff homer to Elly De La Cruz in the first inning. After two scoreless frames, Eugenio Suárez got to him for a solo shot in the fourth. The Reds added a third run on a walk, single, and sacrifice fly in the fifth. Castillo would give the Mariners two more scoreless innings, ending with a quality start. He struck out three. The 33-year-old right-hander will take a 4.85 ERA, 1.33 WHIP, and an 84/30 K/BB ratio across 94 2/3 innings into a start against the Dodgers in Los Angeles next week.

Castillo escaped a bases-loaded jam in the first inning when he induced Victor Mesa Jr. to pop out, ending the threat. The Rays would score their first run of the night off Castillo in the third inning when Chandler Simpson singled to drive home Junior Caminero, and Richie Palacios would homer in the next inning to put the Rays up 2-0. Castillo would surrender two more solo homers in the fifth inning before being pulled to start the sixth, tying a career-high with three homers allowed in this one. Its been a forgettable season thus far for Castillo, who enters the All-Star Break with a 3-8 record and a 4.93 ERA.

Unfortunately, three of the five hits came in a four-batter span in the third inning, producing both runs. That was enough to doom him in what turned out to be a 2-0 game. Castillo has a nice 2.72 ERA and a 30/9 K/BB in 36 1/3 innings over his last seven appearances. If there are no changes, he’s currently in line to make his next start Thursday against the Marlins.

The 33-year-old right-hander punched out four opposing hitters on the night while issuing one free pass. The Guardians scratched out a run against him on an RBI double by Kahlil Watson in the third inning, but that was all that they could muster. Castillo generated 10 swings and misses on 91 pitches on the night, posting a CSW of 26 percent. He’ll attempt to replicate this fine effort when he takes the ball next week against the Angels.

He’s not the first reliever to give up five runs to the Red Sox since Tanyon Sturtze in 2008, but it doesn’t seem totally unrealistic, does it? The Mariners are piggybacking their six starters through the All-Star break, and it seemed like Castillo would get a start the next time through after relieving tonight. However, it was already very clear that he should be sixth in line for starts, and it’s hard to understand why it’d make sense to pitch any of the Mariners’ other five starters behind him next week.