Minnesota Twins relief pitcher Go Woo-suk throws against the Chicago Cubs during the eighth inning of a baseball game in Chicago, July 19. AP-Yonhap

Minnesota Twins minor league pitcher Go Woo-suk has been suspended for 10 games after getting caught with an illegal substance in his glove in a recent Triple-A game.

Minnesota media reported Sunday (U.S. time) Go began serving his suspension Saturday, a day after he was ejected for having a foreign substance in his glove.

The Korean pitcher was traded by the Detroit Tigers to the Twins on July 5 and made his major league debut four days later. He was optioned to Triple-A St. Paul last Tuesday after posting a 9.00 ERA in four outings with the Twins.

Go was about to pitch in the seventh inning for his St. Paul debut Friday but was ejected after an umpire discovered an illegal substance inside his glove.