TEMPE, Ariz. — Carson Palmer was going through the NFL’s concussion protocol on Monday and Arizona coach Bruce Arians said he wasn’t ruling out the quarterback for Thursday night’s game at San Francisco.

The loss of Palmer would be another blow to an Arizona team stumbling to a 1-3 start.

Palmer’s head slammed to the turf late in the Cardinals’ 17-13 home loss to the Los Angeles Rams on Sunday. Arians said that after the game he thought there was no chance Palmer would be back on a short work week.

But the coach said Monday he was encouraged about Palmer’s condition and a decision will be made on whether he plays about the time the team boards the plane Wednesday.

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