TEMPE, Ariz. — On the third play from scrimmage in Sunday’s loss to the Philadelphia Eagles, Arizona Cardinals QB Carson Palmer was strip-sacked by Trent Cole, forcing a fumble that ultimately led to a touchdown.

That play may end up costing the Cardinals more than seven points.

Palmer hurt his right elbow on the play, and though he went on to pass for 302 yards, three touchdowns and two interceptions in the game, he’s been limited in practice all week because of it. As of Friday, it’s possible the quarterback will be unable to go Sunday when the Cardinals host the St. Louis Rams in an important late-season game.

“It will be a game-time decision, he’s listed as questionable,” Arians said. “But I’ve got all the confidence in the world he ain’t missing (the game).”

Arians’ optimism may be comforting, but the official designation Palmer has on the injury report indicates there is a “50-50 chance he will not play.” What it will come down to, the coach said, is how Palmer looks during pregame warm-ups.

It will be the real test after Palmer received limited work this week in practice, though the coach said that is not much of an issue for Sunday since the veteran, like the rest of the team, has a good understanding of the offense.

“Sometimes it’s good at this time of year to give a veteran a couple days off and let the young guy get some reps anyway,” he said. “But I have no problem. He got every mental rep that he needed to and I’m sure he’s going to be fine throwing the ball.”

Should Palmer be unable to go, though, Drew Stanton will take his place under center. Arians says he’s confident in his backup signal caller, but having to play without Palmer would be a bit of an issue.

“It’s huge,” he said of having the starter available. “You really can’t measure it. You can, in a lot of ways, wins and losses around the league, who doesn’t have their guy? It’s a struggle.”

Signed as a free agent by the Cardinals before the team traded for Palmer, Stanton has yet to take a regular season snap for the team. He spent last season in Indianapolis with Arians, so he knows the offense and the coach believes a lack of playing time will not be an issue for Stanton if he has to fill in for Palmer.

“If it comes to that, we’ll deal with it and Drew will do a hell of a job, there’s no doubt in my mind,” he said.

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