The White Sox recalled Schweitzer from Triple-A Charlotte on Saturday.
Schweitzer will join the big-league bullpen as the replacement for Brandon Eisert, who was traded to Pittsburgh on Friday. Schweitzer, 25, has allowed four earned runs in eight frames with the White Sox but owns a 5.08 ERA and 1.43 WHIP across 44.1 innings at Charlotte. He'll likely slot in as a middle reliever.