Palmer hurt again as Cardinals move to league-best 8-1

Cardinals quarterback Carson Palmer injured his knee Sunday and had to be carted to the locker room during the fourth quarter of Arizona's 31-14 win against the St. Louis Rams.

Palmer, who signed a three-year, $50 million extension Friday, tore ligaments in his left knee, a person familiar with the injury told USA TODAY Sports. That person spoke on the condition of anonymity because the team has yet to reveal the extent of Palmer's injury.

It's the same knee Palmer had to have surgically reconstructed when he tore his anterior cruciate and medial collateral ligaments while leading the Cincinnati Bengals during the 2005 playoffs.

Sunday, Palmer's plant leg buckled as he stepped up in the pocket attempting to avoid a sack by Rams safety Mark Barron. Palmer limped to the sideline and grimaced in pain before being carted away.

Coach Bruce Arians said Palmer would undergo an MRI to determine the extent of damage.

Arizona proved earlier this season it can win without Palmer, winning two of three games while he was out with nerve damage in his throwing shoulder.

Sunday, backup quarterback Drew Stanton stepped in to help the Cardinals come back from a 14-10 halftime deficit as Arizona improved to a league-best 8-1.

Stanton, a 30-year-old journeyman, has a 4-3 career record, including 2-1 this season for the surprising NFC West leaders.

The Cardinals suddenly appear to be Stanton's team, beginning Sunday when they host the 7-2 Detroit Lions and Nov. 23 when they go on the road against the defending Super Bowl champion Seattle Seahawks.

Stanton and Arizona's top-ranked defense didn't miss a beat in rallying the team boasting the league's best record.

Stanton came on to fire a 48-yard touchdown to rookie receiver John Brown that put Arizona up 17-14 with 7:40 remaining. The Cardinals defense added two additional touchdowns to help seal the win.

Follow Jim Corbett on Twitter @ByJimCorbett.

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