Carson Palmer doubtful, source says

The expectation within the Oakland Raiders organization that quarterback Carson Palmer would start Sunday against Kansas City has shifted. Two people familiar with the situation now believe it is unlikely Palmer will start.

No final decision has been made.

"I'm 95 percent sure he is not going to play," one source close to the situation said Friday afternoon. "Practicing Wednesday and Thursday, he felt he's not ready to make those high-velocity throws yet. Maybe they could decide something at the last minute, but I don't think he's going to play."

When Oakland acquired Palmer this week, certain Raiders coaches expected their new quarterback would start Sunday, though head coach Hue Jackson has maintained Palmer will be a game-time decision.

Raiders offensive coordinator Al Saunders even told a Kansas City radio station that if Palmer "is breathing, he's playing."

But as the week has gone on, and Palmer has shared reps with both Kyle Boller and Terrelle Pryor, it has become obvious that it would not be a simple transition from injured Jason Campbell to Palmer.

Aside from the physical concerns with Palmer, who before this week had not practiced this season while holding out from the Cincinnati Bengals, there are mental ones as well. If the Raiders resisted the urge to start Palmer on Sunday, they then would have two weeks to prep him before their next game at home against the Broncos. Oakland's bye weekend is next weekend.

Adam Schefter is ESPN's NFL Insider.