Jeff Fletcher of the Southern California News Group noted this means Trout won't play until at least Monday.
Trout has missed extended periods of time the previous two years. Last season, he sat out 19 games in August because of a wrist injury.
The summer prior, Trout was placed on the disabled list for the first time in his career when he underwent surgery to repair a UCL tear in his left thumb. The injury happened when he slid into second base May 28.
Trout returned to the lineup July 14.
In March, Trout signed a 12-year extension worth more than $430 million. The seven-time All-Star and six-time Silver Slugger winner gave the Angels every reason to lock him down for a decade-plus. The star player has led the American League in runs (2012-14, 2016), RBI (2014), stolen bases (2012) and on-base percentage (2016-18), among other categories.
So far in 2019, Trout has hit for a .406 batting average with five home runs and 12 RBI across 12 games.
The Angels, who have yet to win a postseason series since Trout's 2011 debut, are 7-6 and in third place in the AL West.