PITTSBURGH – It was more than just coincidence that on the same day the Steelers re-discovered their identity they re-discovered the player who is linked so closely to it.

"This game set up for me in terms of the conditions and the field," said Jerome Bettis. "I get a head of steam going, and they have to play off blocks, and it’s hard for those guys to stay in there and get leverage on me. So this type of weather is very beneficial to me."

The weather cooperated, and the Steelers took care of the rest in a 21-9 win over the Bears on Sunday at Heinz Field in a game that snapped Pittsburgh’s three-game losing streak at the same time it ended Chicago’s eight-game winning streak.

The field was soft and the snow was thick and the footing was iffy, but to Bettis these were perfect conditions in which to ply his trade. Bettis is the NFL's No. 5 career rusher, but this season he has been serving as a backup, as a change-of-pace for starter Willie Parker. But in a game that screamed for a snow-plow instead of a sports car, Bettis churned out two touchdowns and 101 yards rushing to help the Steelers win a game and right themselves at least temporarily in a season that has three more ultra-competitive weekends to go.

"We live to fight another day. That’s basically where we’re at," said Coach Bill Cowher. "We have no margin of error. Our team did a great job by coming out with a fast start. The 45-yard screen pass (to Willie Parker) was a big lift for us. On the other drive, Hines [Ward] made a great run after the catch for the touchdown. I can’t say enough about our offensive line. Our offensive line did a heck of a job today. They’ve taken a lot of heat, so to speak. I thought they stepped up against a very good football team."

A season-long lack of offense finally caught up to the Bears (9-4) as their normally exceptional defense was merely average, failing to generate any turnovers despite a day seemingly made for mistakes. Instead, it was made for the 260-pound Bettis, a power runner who doesn't need snow tires when the temperatures fall and the going gets rough.

Bettis, held to 22 yards on 14 carries in his previous two games, had his first 100-yard game in the regular season since getting 117 on Dec. 26 against Baltimore. Bettis' previous season high was 56 yards against Cincinnati on Oct. 23, and he had only 186 yards in Pittsburgh's first 12 games.

"He was classic Jerome Bettis," said Cowher. "[It was] a great field for him. He is what he is. He’s a warrior. He’s such a powerful runner. I can’t say enough about him, and what he means to this team."

But even before Bettis got to rolling through the Bears defense like a runaway snowball, the Steelers were doing more of the kinds of things they need to do to win games, things they hadn’t been doing consistently in the losses to Baltimore, Indianapolis and Cincinnati.

Their defense allowed the Bears to drive to a first-and-goal at the 2-yard line, but then it forced them to settle for a field goal. Their offensive line, despite playing without starting left tackle Marvel Smith, did a fine job of neutralizing Bears defensive ends Alex Brown and Adewale Ogunleye to allow Ben Roethlisberger to make some plays in the passing game to help stake the Steelers to an early lead.

On the game’s second play, Roethlisberger flipped a screen pass to Parker, who used blocks by Alan Faneca and Jeff Hartings to turn it into a 45-yard gain that got the offense off to a good start against a tough defense. Then Hines Ward punctuated that possession by taking a short pass and breaking a handful of tackles on the way to turning it into a 14-yard touchdown and a 7-0 lead.

After that, the Steelers (8-5) played a nearly error-free game to thrust themselves back into an AFC playoff picture during a day that ended with losses to Jacksonville, San Diego and Kansas City.

"We were desperate," Ward said. "It's a one-game season every week for us. We've got to play like it's the playoffs, because we don't have a lot of room for error."

The Bears answered the Steelers touchdown by driving the ball to that goal-to-go situation, but the Pittsburgh defense then did what it couldn’t against the Bengals. Aaron Smith made the tackle on a first-down run; Clark Haggans wasn’t influenced by the run-action and therefore was in position to sack Kyle Orton on an attempted bootleg on second down; and then two defensive backs had Desmond Clark covered when a third down pass sailed over his head.

The Bears punted on each of their next five possessions while the Steelers were building a 21-3 lead with two touchdowns runs from Bettis, who also rushed for 100 of his game-high 101 yards in the second half.

After three straight weeks of sub-par play, the offensive line took over the game.

"We didn’t make many errors today up front," Alan Faneca said. "And I think the coaches put us in a good game plan. They put us in a spot to succeed."

Steelers' three touchdowns matched a season high against the Bears, and they outgained the Bears 363-268 and outrushed them 190-83.

"We saw something in the Bears defense that made us think we could run the ball against them," Roethlisberger said. "We wanted to get back to what the Pittsburgh Steelers are supposed to do."

GAME NOTES: Bettis now is fifth on the NFL’s all-time list with 61 100-yard games; he has a team record 50 with the Steelers. Bettis also passed Norm Johnson for fourth place on the Steelers’ all-time scoring list. … On a third-and-3 from the 45-yard line, a pass to Verron Haynes gained 2 yards, and Hines Ward also was flagged for offensive pass interference on the play. Instead of declining and forcing the Steelers to punt, Bears coach Lovie Smith accepted the 10-yard penalty. Roethlisberger converted with a 16-yard pass to Haynes, and the Steelers eventually scored the touchdown that gave them a 14-3 lead … Willie Parker gained 43 yards on his first nine carries, but included in that were gains of 11, 11, 9 and 8 yards ... The teams combined for six fumbles (Steelers 4, Bears 2) but none became turnovers ... Ward’s touchdown was the 51st of his career, and that tied him with Lynn Swann for second on the team’s all-time list ... Roethlisberger is 19-3 as a starting quarterback.