Pujols took a pitch from A's left-hander Sean Manaea to the same foot that was surgically repaired in the offseason, leaving the game after the third inning.
The injury was diagnosed as a bruise and Pujols, who was serving as the DH, was listed as day-to-day.
The Pujols injury was tempered with good news for the Angels, who got back Jered Weaver after the right-hander missed about two weeks with a neck injury.
Weaver, whose injury was diagnosed as degenerative changes in the cervical spine, threw five solid innings, giving up three earned runs on five hits and striking out two in his third start.
Information from The Associated Press was used in this report.