Rockies shortstop Troy Tulowitzki ruled out by injury

NEW YORK (Reuters) - Colorado Rockies shortstop Troy Tulowitzki has torn a tendon in his left quadriceps and could be sidelined until at least the All-Star break, the team said on Thursday.

The 23-year-old, runner-up for the 2007 National League rookie of the year award, suffered the injury during the first inning of Tuesday's game against the San Francisco Giants.

"Best-case scenario is six weeks but it's possible it could take a couple of months or more," Tulowitzki's agent Paul Cohen was quoted as saying on Colorado's official website (www.colorado.rockies.mlb.com).

Tulowitzki, who signed a six-year, $31 million contract during the off-season, was hitting .152 with one home run and 11 RBIs in 105 at-bats this season.

Clint Barmes, the Rockies' starting shortstop in 2005 and 2006, returns to his former job in Tulowitzki's absence.

(Writing by Mark Lamport-Stokes in Los Angeles; Editing by Ed Osmond)