Raiders quarterback Jimmy Garoppolo ruled out against Chargers

Jimmy Garoppolo was ruled out of Sunday's game at the Los Angeles Chargers because of a concussion, making the Las Vegas Raiders starting quarterback a mystery.

Either 15-year veteran Brian Hoyer or rookie Aidan O'Connell will start in place of Garoppolo, who has been in concussion protocol after getting injured Sunday night against the Pittsburgh Steelers. The Raiders didn't announce which one would get the nod.

Also, the Raiders announced that starting cornerback Nate Hobbs will not play because of an ankle injury, and running back Brandon Bolden didn't make the trip to Los Angeles because of personal reasons. Bolden, however, will travel to LA on his own and is expected to play.

Las Vegas coach Josh McDaniels was noncommittal when asked earlier in the week which quarterback he might go with against the Chargers.

"I think everybody is going to get ready to go, and I think sometimes experience is a good thing," McDaniels said. "It doesn’t mean that it’s going to determine how it’s going to go for one guy versus another. There are a lot of guys that don’t have a lot of experience that can play well because they’re prepared, and they do the right thing to get ready. Ultimately, what matters is how they perform, not how long they’ve been in the NFL or how many games they’ve played in or what have you."

Hoyer and McDaniels go back to New England when the QB was Tom Brady's backup and McDaniels was the Patriots' offensive coordinator.

"I've been a starter, I've been a backup," Hoyer said Thursday. "The mentality is always prepare to play and then go out and execute when your name's called."

O'Connell was drafted this year in the fourth round out of Purdue and had a strong preseason. He completed 69.4% of his passes for 482 yards, with three touchdowns and no interceptions in three preseason games. He started two of them.

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At some point, especially with a quarterback-rich draft next year, the Raiders will have to determine if O'Connell is their QB of the future or if they need to look elsewhere. That could be a determining factor in McDaniels' decision on which player to start.

Reporting by The Associated Press.