For the Rams, it was trying to cobble together a representative backfield performance with Steven Jackson sidelined for the third time in a month with a strained thigh muscle.

Those goals generally were achieved Sunday. But the ultimate goal - a victory over NFC West rival San Francisco - proved to be far more elusive. The 49ers rolled up a commanding halftime lead and cruised to a 35-16 win in front of 67,573 at Candlestick Park.

Pittman, who started his fourth game in a row at running back, acknowledged that he's "enjoying it a lot." But he added firmly:

"Anybody can enjoy going out there and enjoy being the starter. But any guy who's got pride and puts it all on the line and has got some heart in this business would enjoy a victory even more."

Pittman and Darby, both second-year pros with scant experience before Jackson's injury, combined for 208 total yards, a solid average of 6.5 yards every time they touched the ball.

Pittman carried 14 times for a career-high 95 yards, and his three receptions netted 4 yards. Darby ran for 26 yards on seven tries and added 83 yards on eight catches.

"They did a great job filling in," quarterback Marc Bulger said. "It's not easy coming in and out of the games like they're doing right now, but they're doing a good job with it."

Overall, the Rams churned out 126 yards on the ground, the most since they amassed 180 vs. Dallas on Oct. 19 and their third-highest total of the season. They came into the game with the 26th-ranked rushing offense among the NFL's 32 teams.

"You've got to look at the bright spots," center Nick Leckey said. "If we can run the ball like that, then that's something we can look at and say, 'Hey, that's one thing we're doing well.'''

Darby, signed off Atlanta's practice squad Oct. 14, fumbled twice last week against the New York Jets. Although the second bobble was negated by a Jets penalty, Darby was ordered to the bench. Coach Jim Haslett said later that he considered cutting Darby the next day.

But with Jackson still ailing, Darby got a second opportunity. He was fumble-free vs. the Niners.

"I'm very grateful that the coaches gave me another chance, that they didn't give up on me," he said. "I know they see potential in me, and I wanted to show them that what happened last week was a fluke, because I'm not the type of back to put the ball on the ground."

Darby caught just two passes in brief action last season with Tampa Bay. His heavy role as a receiver Sunday "pretty much developed as the game went on," he said. "I thought I was going to get a lot more carries than I did, but I'm not complaining whatsoever. Whatever I can do to help my team win, that's what I'm going to do."

On Friday, Haslett challenged Pittman to prove that he deserved to get the bulk of the work in Jackson's stead. "He needs to show that he's a back that can play in the league for a long time," Haslett said.

That challenge hasn't been met, Pittman maintained, for two reasons: The Rams lost, and they settled for field goals three times before finally getting a late touchdown on a 2-yard pass to wide receiver Dane Looker.

"I take full blame," he said. "When we got into those situations on the goal line, we have to punch it in. I didn't play my part in that role."