The move was made retroactive to Saturday, when Ward was held out of the Angels' lineup because of the injury.
"It's not awful," Angels manager Joe Maddon told reporters, according to MLB.com. "It just needs attention. The conversation indicated that hopefully it'll be the minimum amount of time. We're hoping it's not more than that."
It's the latest injury for Ward, who has also battled a groin injury and a neck stinger this season. Despite that, Ward is so far enjoying what could be a career-best season, hitting .333 with 10 home runs and 26 RBIs.
The Angels recalled outfielder Jo Adell to take Ward's spot on the 26-man roster.
Adell went 1-for-4 with an RBI in the Angels' 9-7 loss Sunday to the Philadelphia Phillies. The loss Sunday was the Angels' 11th straight, dropping their record to 27-28.