Ross hurt himself chasing down a flyball in a game Wednesday. The MVP of last year's NL championship series had an MRI exam Thursday that confirmed the injury.
The Giants have several options to replace Ross in right field when the regular season begins next week. Andres Torres could shift over from center field or Aubrey Huff could move from first base, leaving rookie Brandon Belt at first.
Nate Schierholtz also is a candidate. He was set to start in right Thursday night against Cleveland.