The White Sox have outrighted Simon Castro off the 40-man roster to Triple-A Charlotte.
The right-hander was 0-1 with a 2.70 ERA in four games for the White Sox. He made his major league debut in July but performed poorly after he was sent back to Charlotte.
Castro appeared in 27 games (12 starts) at Charlotte and went 3-7 with a 5.83 ERA and 82 strikeouts in 92 2/3 innings.
The White Sox now have 36 players on their 40-man roster.