The Athletics made the move on Tuesday before they opened a series against the Twins in Minnesota. But Reddick was not in the lineup.
Reddick was placed on the disabled list on Aug. 26 with a sprained right wrist. The wrist has bothered Reddick for most of the season, stemming from a crash into the wall in Houston in April.
Reddick is hitting .213 with 10 homers and 46 RBIs in 97 games.
The A's also got third baseman Josh Donaldson back in the lineup after he sat out the previous game with a sore right quadriceps.