Mariners Trade Luis Castillo To White Sox

Luis Castillo traded to Sox

Mariners deal struggling Luis Castillo to White Sox in three-player trade. White Sox acquire Luis Castillo from Mariners, take on $70m+ remaining. 

White Sox land Luis Castillo as Mariners clear salary in trade...

The Seattle Mariners dealt starting pitcher Luis Castillo to the Chicago White Sox on Saturday, receiving reliever Seranthony Dominguez, outfielder Nolan Jones, and catching prospect Boston Smith in return.  

Castillo, 33, has posted a 5.06 ERA across 99.2 innings this year with 86 strikeouts. That’s a steep drop from his last three seasons, when he pitched below a 3.70 ERA each year, including an All-Star 2023 campaign that saw him finish fifth in AL Cy Young voting.

Chicago will cover the prorated share of his $22.75 million salary for the rest of this season, the full $22.75 million in 2027, plus a $25 million vesting option for 2028.

Dominguez, 31, will be joining his fourth team in three years. He’s putting together a solid 2026, with a 3.99 ERA in 41 appearances and 12 saves. Opponents are hitting just .201 against him this season. In 38.1 innings, the veteran has 47 strikeouts to 28 walks and has allowed 28 hits.

White Sox reportedly acquire RHP Luis Castillo from Mariners, per multiple reports including MLB's @Feinsand.

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Jones, 28, is batting .257/.362/.445 in Triple-A this year with 14 home runs, 59 RBI, and 11 stolen bases in 90 games.

Smith, 23, is hitting .291/.448/.589 across Single-A, High-A, and Double-A, with 22 home runs, 58 RBI, and nine steals in 78 games combined.