The White Sox outrighted right-hander Zach Stewart to Triple-A Charlotte on Tuesday, clearing a spot on the team's previously-full 40-man roster. With the addition of reliever Matt Lindstrom last week, the team had all 40 spots on the roster filled, meaning a player would have to be removed from it to make another addition.
Stewart will still be in big-league camp next month as a non-roster invitee. The 26-year-old was dealt from the White Sox to the Red Sox last June as part of Boston's return for Kevin Youkilis.
Over two major-league seasons, Stewart has a 6.82 ERA in 103 innings split between the starting rotations and bullpens of the Blue Jays, White Sox and Red Sox.