Derek Carr's demeanor has stayed remarkably the same even as the losses keep piling up for the winless Oakland Raiders.

If the pressure and strain of an 0-9 start is wearing on the rookie quarterback, Carr isn't showing it.

"He's a mature guy, a mature player," wide receiver James Jones said Wednesday. "He understands at a young age that there are going to be times like this, in your career and in your life. You take it and run with it, you don't put your head down. You look at it in the face and you fight it."

The Raiders are riding a 15-game losing streak that predates the arrival of Carr, Oakland's second-round draft pick this year. They are the only winless team in the NFL and are trying to avoid becoming just the second in to go 0-16 in a season.

Carr played fairly well during the first two months but has regressed the past two weeks. He has thrown four interceptions in the previous two games and has completed only one pass longer than 25 yards in that time.

That has raised concerns whether Carr is capable of being the franchise quarterback, though interim coach Tony Sparano has been quick to defend him.

Not that he needs it.

The 23-year-old Carr has a poise that many veterans lack. He insists his confidence is high and that he isn't feeling the heat from critics or fans.

"To be honest, if you were to come and just hang out in our locker room or hang out in our meetings, guys are driven to get better," Carr said. "When the effort goes down, that's bad. The energy level is honestly like we're 9-0. Guys are running around still striving to do what they can to make this thing right.

"Hopefully it will be sooner than later, but it's going to happen one of these days."

With little support from the running game to keep defenses honest, the Raiders have been unsuccessful in trying to stretch the field with the passing game.

Carr completed only 58.5 percent of his throws and was picked off twice against the Seattle Seahawks. He followed that with two more interceptions last week against the Denver Broncos.

He came back to throw a late touchdown in the loss to Denver and was thankful Sparano left him in the game despite the lopsided score.

"I should be out there no matter what, good, bad or ugly," Carr said. "And for a long time it was ugly. For me it was important to continue to finish. I wanted to go out there and compete one last time and try to correct the things we'd been trying to correct all game. We got to do that."

Carr had his best game of the season in Week 6 when he passed for 282 yards and four touchdowns in a 31-28 loss to San Diego.

The Raiders play the Chargers again this Sunday in what Carr says is his first time facing the same team twice in one season.

"One thing for me is you know their personnel," Carr said. "For me as a rookie, that's always something that's unknown. You can see something on film, but until you're really out there playing against somebody and you see him for the first time, you don't really know. So that's something that's really helpful."

NOTES: Right tackle Menelik Watson was held out of practice but did conditioning work on the side. Watson sustained a concussion in the loss to Denver. Second-year player Matt McCants took reps with the first-team offense in Watson's absence. ... Defensive end Justin Tuck woke up with a sore neck and didn't practice, though Sparano didn't think it was serious. ... Cornerbacks DJ Hayden (groin) and Carlos Rogers (knee) were also held out. ... Spencer Hadley, a rookie linebacker on the practice squad, took reps at fullback. Jamize Olawale (shoulder/hamstring) rested.