Manager Brad Ausmus announced the injury Tuesday. He says Upton has "turf toe" and that no timetable has been determined for his return. Upton was injured in Sunday's exhibition game against the Los Angeles Dodgers when he bumped into the left-field wall while chasing a fly ball.
Upton had just returned after missing most of spring training because of tendinitis in his right knee.
Ausmus said Peter Bourjos will likely see more playing time until Upton returns, but he is still waiting to solidify a plan moving forward.
Upton, 31, hit 30 home runs with 85 RBIs over 145 games last season, his second with the Angels.
The Angels also announced Tuesday that right-hander Jaime Barria will start the season at Triple-A Salt Lake. Barria was 10-9 over 26 starts as a rookie last season, posting a 3.41 ERA.
The Angels also got closer to a final bullpen with the announcement that left-hander Dan Jennings had been released.