Mike Trout, the Angels' superstar center fielder who has been hampered by a litany of injuries in recent years, suffered a torn meniscus in his left knee that will require surgery.

The Angels did not announce a timetable for Trout's recovery while revealing the injury Tuesday, but sources familiar with the situation said a best-case scenario could be four to six weeks. A true timeline, however, can't be determined until doctors take a closer look at Trout's knee. Surgery is expected to take place at some point this week, with a source indicating it could happen Friday.