Ko Woo-seok Minnesota Twins pitcher

In early July 2026, the Minnesota Twins acquired South Korean reliever Ko Woo‑seok from the Detroit Tigers in a cash trade, guaranteeing his spot on the Twins’ 26‑man major‑league roster. The move marked Ko’s entry as the 30th Korean player in MLB, with the Twins hoping his strikeout ability and low home‑run rate would bolster a struggling bullpen.

After making his major‑league debut, Ko was optioned to the Triple‑A St. Paul Saints. On July 25, umpires inspected his glove during his Triple‑A debut, found an illegal foreign substance, and ejected him without a pitch. Under MLB’s 2021 rule, the violation triggered an automatic ten‑game suspension, applied retroactively from July 26. The Twins said they will not appeal. The suspension delays his return to the majors and further jeopardizes his promotion prospects, forcing the Twins to adjust their minor‑league pitching depth while the league continues its crackdown on illegal grip enhancers.