ALAMEDA, Calif. (AP) — Raiders quarterback Derek Carr was limited for a second consecutive practice Friday and coach Jack Del Rio declined to say what, if any, role Carr will have this weekend against the Baltimore Ravens.

Carr broke a bone in his back late in the third quarter of Oakland's 16-10 loss in Denver this past Sunday. He was initially diagnosed with back spasms but the injury was later revealed to be a transverse process fracture.

Earlier this week, Del Rio indicated that Carr would miss the Baltimore game and possibly up to six weeks but the fourth-year quarterback was cleared for light practice Thursday and Friday and is listed as questionable.

Carr leads a long list of players on the injury list. Del Rio declined to discuss any of them.

"Before you even have to ask, there are a lot of question marks on the injury report and that's what they are," Del Rio said. "I'm not going to really talk about injuries and what we may and may not do or who we may or may not play or when and all that kind of stuff, when we're going to utilize people. Not going to get into all of that.

"We do have a number of people who are questionable. We have time before we tee it up. They'll remain a question mark until we make the final decision."

The Raiders have already named EJ Manuel as the starter for Sunday. The 16th overall pick in 2013, Manuel has started seven games since his rookie season and will be tasked with trying to jump-start an offense that has been held to 10 points in each of the last two weeks.

"I've been in this situation before even when I was in college," Manuel said. "Then when I was in Buffalo, when Tyrod (Taylor) became the starter, still just being ready as the backup. It kind of puts me in familiar territory."

Connor Cook, a fourth-round draft pick in 2016, also is on the roster but has been inactive in each of Oakland's first four games.

The Raiders have been mostly quiet regarding Carr's status this week, although left tackle Donald Penn told reporters Thursday that the quarterback was ahead of schedule in his recovery.

It's conceivable that Carr could suit up for the Ravens game as the team's emergency quarterback, but Del Rio isn't saying.

"We prefer to keep our business in house," Del Rio said.

Cornerback David Amerson has cleared the NFL concussion protocol, according to Del Rio. Like Carr, Amerson was limited in practice and is questionable.

Notes: Right guard Gabe Jackson (foot), cornerback Gareon Conley (shin) and running back DeAndre Washington (hamstring) were limited in practice and are questionable. Jackson had not practiced at all this week.

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