"Of course he brings the running ability, but he's trying to be a leader out there, have command of the huddle and doing the job that a starting quarterback should do," receiver Darrius Heyward-Bey said.
Leinart had hoped to be able to make his third start since 2007 but thought the Raiders might give the nod to Pryor to see what he can do in a real game.
"The competitor in me wants to play, wants to start, but I do understand that they need to evaluate him, and I get that," Leinart said. "Obviously, you're not happy by any means, but at the same time I'm a team player. I've learned a lot this year, and I'm happy to help."
The Raiders also could have a new starter on the offensive line as starting right guard Mike Brisiel missed his third straight practice as he recovers from an ankle injury and concussion.
Brisiel, one of Oakland's biggest free-agent signings this past offseason, has struggled in his first season with the Raiders. He has committed a team-high 10 penalties and been part of a running game that has struggled to generate any consistency.
Brisiel is listed as questionable and will be a game-time decision. If he can't start, rookie Tony Bergstrom would get the nod. Bergstrom was Oakland's top draft pick in April at 95th overall but has struggled to get on the field. He has played eight games this season and gotten 75 snaps on offense, with most coming as a tight end in Oakland's six-linemen alignment.
"He's going to go through some growing pains like any new player would," offensive coordinator Greg Knapp said. "I feel good about him. I like what I've seen in practice. I also have seen the rookie mistakes that I know this might show up in a game. But I'm looking forward to get him some reps to see him play live."
NOTES: CB Phillip Adams will be placed on IR with a groin injury and be replaced in the lineup by Brandian Ross, who has played well as a reserve in recent weeks. ... DB Cory Nelms and DL Brandon Bair will be activated from the practice squad for Sunday's game. S Tyvon Branch (neck, ankle) returned to practice Friday and is listed as questionable.
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