TEMPE, Ariz. (AP) In his 12th NFL season, Carson Palmer was having the time of his life.
A career of big numbers but little team success was reborn in the desert, where the Arizona Cardinals, at 8-1, have the best record in the NFL.
Then on Sunday, as the 34-year-old quarterback tried to evade a blitzing St. Louis Rams safety, he felt his left knee give way.
Palmer knew immediately that his season was over.
''I didn't need an MRI or an X-ray,'' he said. ''I felt a pop so I knew it was my last time on the field this year.''
Tests confirmed that it was a torn left ACL, the same knee he injured even more severely in a 2006 playoff game while with the Cincinnati Bengals. The injury came two days after he signed a three-year contract extension worth $50 million, with $20.5 million guaranteed.
Surgery will wait for another two weeks to allow the swelling to subside. The team hopes he will be ready for OTAs next summer.
On Monday, Palmer hobbled into the Cardinals' media room on crutches and spoke about the emotional pain.
''It's not easy,'' he said. ''I'm not going to lie. I cried like a baby last night and I'm not an emotional guy. The last time I cried like this was when I lost my friend and teammate Chris Henry back in `09.''
Palmer seemed to finally be within reach of the kind of season so many had expected of him when he was drafted No. 1 overall by the Bengals in 2003. A Heisman Trophy winner at USC, he stood 6-foot-5 with a cannon arm.
Huge statistical years followed, wins and playoff appearances didn't.
A year ago, Palmer came to Arizona from Oakland, joining coach Bruce Arians, who at 60 finally got a chance to be an NFL head coach.
The parallels were obvious.
''Like an old cowboy movie,'' Arians said at the time. ''This is our last rodeo in the desert.''
After struggling with the intricacies of Arians' offense for the first half of last season, Palmer eventually grew more comfortable. Arizona won seven of its last nine to finish 10-6, barely missing the playoffs.
This season, Palmer went down in the opener with a damaged nerve in his throwing shoulder. He missed the next three contests, with backup Drew Stanton going 2-1. Palmer returned and Arizona kept winning, going 8-1 for the first time since 1948, when they were the Chicago Cardinals.
''That's probably the toughest part,'' he said. ''I'm having more fun than I've ever had in my entire career. I'm on the best team I've ever been on, a phenomenal group of guys from the top down.''
Arizona has won 13 of Palmer's last 15 starts. This season, they are 6-0 with him. He has thrown for 11 touchdowns with three interceptions.
Elated with Palmer, the Cardinals signed him last Friday to the three-year contract extension.
With the Super Bowl to be played in Arizona next February, the Cardinals had visions of playing the big game on their home field, with Palmer leading the way.
''It's hard,'' Arians said. ''I knew walking out on the field what I was going to find. You're pulling for a guy because he's put so much into it to get into the playoffs and win some games and maybe go all the way because you know what it means to him at this point in his career.''
Palmer vowed that he would play football again.
There was no contact when Palmer was hurt. He had stepped up to avoid blitzing safety Mark Barron.
''I've done that move thousands of times,'' Palmer said. ''... My foot hit the grass and the grass gave way. It was just a freak thing.''
He knows what's ahead. Rebuilding his knee nine seasons ago was an even bigger challenge.
In that game, he completed his first pass for 66 yards, was hit and crumpled to the ground. He had signed a $100 million contract extension 10 days earlier, an eerily familiar scenario.
''Crazy,'' he said.
Palmer appeared in only one other playoff game. His team lost them both.
Now any Arizona Super Bowl run will have to come without its starting quarterback and offensive team captain, the latest in an imposing list of Cardinals players lost due to injury.
As a cart wheeled him out of the stadium, Palmer heard the cheers of the fanatic Cardinals ''Red Sea.''
''There's so much electricity in the stadium on Sundays and there's so much hope, there's so much excitement and there's so much faith and belief (from) our fans,'' Palmer said. ''That's not the way you ever want to leave a stadium, but this was a special year to play in front of our fans in our stadium. Nothing says we can't finish this season in our stadium in front of a lot of our fans.''
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