ALAMEDA As running back Darren McFadden turned to address reporters gathered at his locker Wednesday, he bumped a TV cameraman's gear.
"Oh, my bad," McFadden said, grinning. "Man, I'm knocking microphones down. "
If the player the Raiders deemed their "bell cow" this year is frustrated by two lackluster rushing performances to start the season, he isn't showing it.
But McFadden, who averaged 101.7 rushing yards in his first six games last year before getting hurt, has 54 yards on 26 carries as the Raiders have struggled to get anything going on the ground with their new offense.
There are 43 players in the NFL with more rushing yards than McFadden.
"Just going out there and looking at the film, it's hard to say (what the issue is)," McFadden said. "What you don't see much of is many big runs. That's something that I feel like we hang our hats on with our offense is big runs from our running backs, and we haven't got that lately."
McFadden credited "two good defenses" in the Chargers and Dolphins with holding the Raiders to an average of two yards per carry. It doesn't get easier this week against the Pittsburgh Steelers, who perennially are among the NFL's top run defenses.
"Our goal is going to be to run the ball on people, and we're going to do that," quarterback Carson Palmer said. "It hasn't worked the first two games, but we're not going to change anything we're doing."
Falling behind has contributed to the Raiders running the ball just 14 times in the second half, for minus-four yards. But they also have run on just 24.5 percent of first-and-10 plays, lowest in the league, according to the Associated Press.
That has led to frequent long-yardage situations on second and third downs, again prompting them to go to the air. The Raiders have just four first downs this season via running plays, and only the Tennessee Titans, with two, have fewer.
"We're going to do whatever the game dictates that we have to do," coach Dennis Allen said. "If it dictates we should run the ball 50 times, that's what we'll do. If it dictates throwing the ball, that's what we'll do.
"Each game plan is going to be different, and we'll play each game out as they go. But I've got all the confidence in the world in our running game. I've seen it work. It's been successful in this league, and we've got the right personnel to get it done."
Allen defends the Raiders' new zone-blocking scheme that has produced little through two games and raised some questions about McFadden's suitability to it.
McFadden ran primarily behind that kind of blocking, which requires the back to hesitate behind the line before hitting a lane while blockers clear out an area rather than specific defenders, in his first two seasons and averaged 3.95 yards a carry, then averaged 5.27 yards a carry the past two years after the Raiders switched offensive coordinators.
"I just feel like with the zone system, it's one of those situations, you just have to keep hitting it until you get going," McFadden said. "It's going to be one yard here, two yards there, and eventually (it's) going to start popping."
Said left guard Cooper Carlisle: "I'm definitely a believer in the system and I still think it's going to work."
New corner The Raiders signed cornerback Brandian Ross, adding depth to the depleted position. Ross had been on the Green Bay Packers' practice squad, where he spent all of last season.
Allen said the Raiders are still unsure how long Shawntae Spencer (sprained foot) will be out. In Spencer's absence, safety Michael Huff took some reps at cornerback in practice, and Allen said that's likely something that will continue.
Et cetera The Raiders held linebacker Rolando McClain (concussion) out. McClain said he suffered the concussion against Miami, but he couldn't pinpoint the play. Under league protocol, he will have to be medically cleared to return.
Along with Spencer and McClain, right tackle Khalif Barnes (groin) and cornerback Coye Francies (concussion) were listed on the injury report as not practicing.
For the Steelers, safety Troy Polamalu (calf), linebacker James Harrison (knee) and wide receiver Mike Wallace (groin) were among those who did not practice.
The Raiders signed defensive back Akwasi Owusu-Ansah and defensive tackle Vaughn Meatoga to the practice squad.