CINCINNATI (AP) _ Ken Griffey Jr. could be out for five to seven days after partially tearing his left hamstring when he crashed into the catcher trying to score.

An MRI disclosed the extent of the injury after the Reds originally said it appeared to be a strain, the team said Tuesday.

The Cincinnati outfielder could be available for the Giants series next week in San Francisco, depending on his rehabilitation, Reds spokesman Rob Butcher said.

Griffey crashed into Chicago Cubs catcher Joe Girardi during the seventh inning of Monday night's game, won 7-6 by the Reds.

He had walked and was trying to score from first on a double to left field by Dmitri Young. The relay by shortstop Ricky Gutierrez got to the plate well ahead of Griffey, who banged into Girardi and was tagged out.

Griffey lay on the ground several minutes before limping to the clubhouse.