Given the condition of his injured left ankle and that he practiced on a very limited basis, Ben Roethlisberger played beyond anyone's expectation -- passing for 330 yards and never flinching in the pocket. But, in a game where points would be precious, he had two costly interceptions in the first half, a lost fumble and another interception in the fourth quarter. Four turnovers with no takeaways by the defense is not a good combination.
RUNNING BACKS C
The 49ers had not allowed a 100-yard rusher in the previous 35 games, the longest active streak in the league, and that mark was not threatened by Rashard Mendenhall. He finished with 64 yards on 15 carries -- the most by an opponent since Michael Vick had 75 yards in Week 4 -- and bounced several runs off tacklers. That after having nine carries for 30 yards with no run longer than 8 yards in the first half.
WIDE RECEIVERS C
There were some nice individual plays, but those only matter for the highlight film. Jerricho Cotchery had a number of big catches in the second half, and so did Heath Miller. And Mike Wallace had a nice 36-yard catch-and-run on the first possession that ended with the most costly interception. But his biggest mistake was failing to touch down Dashon Goldson after an interception, allowing him to make a 21-yard return.
OFFENSIVE LINE D+
The 49ers had the No. 1 rush defense in the league and had not allowed a rushing TD this season, but the line did a nice job creating some gaps for Mendenhall, even though they were without C Maurkice Pouncey. And Roethlisberger had good protection for most of three quarters until he was sacked and harassed in the fourth quarter. LT Max Starks really struggled with rookie LB Aldon Smith, who had all three sacks.
DEFENSIVE LINE C
The line did not exactly shut down Frank Gore, who rushed for 65 yards on 18 carries. And they didn't generate pressure on QB Alex Smith, who was never sacked. The 49ers finished with 100 yards rushing, not overwhelming numbers. But in a game where someone needed to make a play, the defense came up with none. The 49ers scored twice in the red zone, something they had done only three times in 19 trips in six games.
Playing without suspended LB James Harrison, the Steelers failed to sack Smith, even though he had been sacked 18 times in the previous three games. Lawrence Timmons continues to miss tackles and overrun plays and was victimized on pass plays of 27 and 21 yards on the 49ers first TD drive. It did not help that LaMarr Woodley, who returned after missing most of five games (hamstring), aggravated the injury and did not return.
DEFENSIVE BACKS B
Smith failed to challenge the cornerbacks deep and was content to throw underneath the coverage, especially in the first half when his longest completion was 14 yards. S Ryan Clark had a couple of pass breakups in the first half and SS Troy Polamalu torpedoed a few receivers to hold them to short gains. Smith finished with 187 yards passing, but found other ways to beat the defense, getting the ball to Davis when he was isolated on linebackers.
SPECIAL TEAMS C-
Shaun Suisham finally converted from beyond 50 yards, and it was a big one -- a 51-yarder to cut the lead to 6-3. But he missed a 48-yarder at the end of the third that could have given the Steelers a little momentum. Big tackle on the second-half kickoff by Stevenson Sylvester on Ted Ginn, pinning the 49ers at their 8. Not a good penalty on Timmons on a FG attempt that gave the 49ers a first down and let them to score a touchdown.
Given an opening to finish as the top seed in the AFC, the Steelers could not overcome three turnovers -- all by their hobbled quarterback -- nor get big plays from the defense. It's tough to play on the road without your best offensive lineman and linebacker, especially when one mistake can make the difference. Nonetheless, with a clear path to the No. 1 seed in the AFC, the Steelers failed to beat a winning team on the road again.
Gerry Dulac: email@example.com ; twitter: @gerrydulac