The White Sox selected Schultz's contract from Triple-A Charlotte on Tuesday.
Schultz is set to make his major-league debut with a start Tuesday against the Rays. The 6-foot-10 left-hander earned a promotion after a dominant start to the season with Charlotte, as he posted a 19:2 K:BB over 14 innings to go along with a 1.29 ERA. Control and injuries have been a problem at times for Schultz, but he has some of the best upside of any starting pitching prospect in baseball. He'll get an opportunity to stick around with the big club if he pitches well.