ST. LOUIS -- When Arlen Harris fumbled twice on the punt return in consecutive early-season games to hand touchdowns to the opposition, it could have easily been the end of his Rams career.

Coach Mike Martz has cut players with less provocation. Instead, the missteps are now ancient history and the third-string tailback has emerged as a young talent following injuries to Marshall Faulk and Lamar Gordon.

The undrafted rookie is coming off his second straight solid outing as the emergency back. He scored three touchdowns in his first career start last week at Pittsburgh, rushed for 85 yards on 18 carries and his first touchdown the previous week against the Packers, and hasn't lost a fumble in 52 carries during his stretch in the spotlight.

"There's a toughness about Arlen that you appreciate when you're around him," Martz said. "There's a certain confidence and aggressiveness inside of him. He's not anxious. He's determined and he's prepared."

Harris has progressed to the point that the Rams weren't rushing to get Faulk, the 2000 MVP, back on the field.

Faulk likely will start Sunday at San Francisco after missing four games plus the bye week with a broken left hand and right knee injury. But he'll likely share the position with Harris while Gordon continues to recuperate from a high ankle sprain.

Harris didn't play his senior year at Hofstra because of an eligibility issue following his transfer from Virginia, leading him to undrafted status. Rams running back coach Wilbert Montgomery noted Harris at a workout, and recruited him for the team.

"Hopefully, somewhere down the road, I'll be able to start for a ballclub," Harris said.

For now, he's gratified Martz looked past the fumbles.

"Everybody keeps bringing that back up and that's something I just put behind me," Harris said. "I feel blessed that he has confidence in me and they see there's a bright future with me."