Floyd, whose DL stint is retroactive to Aug. 27, left Sunday's game against the Seattle Mariners after two innings because of elbow discomfort. White Sox manager Robin Ventura said Monday an MRI on Floyd's elbow revealed no structural damage. Floyd was also on the 15-day disabled list in July because of tendinitis in the same elbow.
Floyd is 9-9 with a 4.55 ERA in 24 starts this season.
Axelrod, a right-handed pitcher, has gone 1-2 with a 5.63 ERA in 10 games, including six starts, over two stints with the White Sox this season. He is 7-5 with a 2.88 ERA in 16 starts in Charlotte.
Center fielder Alejandro De Aza was also assigned to Charlotte for an injury rehabilitation assignment. De Aza has been on the disabled list since Aug. 21 (retroactive to Aug. 18) with bruised left ribs. He is hitting .281 with six home runs, 44 RBIs, 73 runs, 21 stolen bases in 111 games this season.
The White Sox hold a two-game lead on the Tigers in the American League Central.