Running back is the big question

The questions surrounding UCLA’s running game won’t be answered until the Bruins play Arizona on Saturday in Tucson.

Has Chris Markey recovered enough from a toe injury to handle the bulk of the work? Is Chane Moline ready for a breakout moment? How much has Christian Ramirez absorbed since moving from safety to running back in August?

Markey, if healthy enough, will do the bulk of the work Saturday with leading rusher Kahlil Bell out for the season with a knee injury.

It’s a familiar role for Markey, who led the Bruins with 1,107 yards last season. He has 449 yards rushing this season but has been used sparingly since the injury against Oregon State on Sept. 29.

“I’m definitely not 100%, but I’m getting there,” Markey said. “I can’t focus on that right now. The team needs me now and I have to step up and perform.”

Markey was limited in practice the last three weeks. He sat out the Notre Dame game, then carried the ball eight times for 19 yards against California. When Bell was injured against Washington State on Saturday, Markey came in and finished with 41 yards in 15 carries.

“The toe felt pretty good, but I was a little rusty as a runner,” Markey said.

Moline and Ramirez are the other options.

Moline, a sophomore, scored five touchdowns rushing in 2006. He was slowed at the start of practice because of a broken bone in his hand. He has 90 yards in 25 carries this season.

“I think he’s on the verge of catching up,” running backs coach Dino Babers said. “We’re still waiting for that breakout game to remind us of the guy of old. . . . Hopefully it will come this week.”

Ramirez remains a project, though Babers said, “he knows the offense better, but he is still pretty rusty as a runner. What he has really improved on is the pass protection and the schemes and routes and stuff. He still hasn’t busted out as a runner.”

Middle linebacker Christian Taylor, who sat out last week with a concussion, returned to practice Tuesday, though he did not participate in contact drills. Taylor is expected to play this week, Coach Karl Dorrell said.

Taylor wobbled off the field against California on Oct. 20, then suffered a small seizure on the sidelines. He was taken to the hospital, but was released that night.

Taylor said the concussion occurred in the fourth quarter. When Cal got the ball back late in the game, “I hit their [running] back with my head lowered a little bit. Then it was kind of like Twilight Zone.”

Taylor said he has scattered recollections from that point. He didn’t even know the Bruins had won the game until his father told him at the hospital.

“I just vaguely remember people around me, then I remembered being at the hospital,” Taylor said.

Receiver Brandon Breazell, who suffered bruised ribs against Washington State, was in pads for practice Tuesday but did not participate in drills.

“He’s better than I expected,” Dorrell said. “I didn’t want him to do too much today.”

Defensive tackle Brigham Harwell, trying to come back from a knee injury, participated in more drills Tuesday but sat out contact drills against the scout team. Quarterback Ben Olson, also trying to return from a knee injury, suited up but was limited to individual drills.

chris.foster@latimes.com