The Steelers will feature an unmovable object when they take Heinz Field for their first playoff game Sunday.

Their No. 1 ranked defense? Yes, that, too. And it's a good thing they have such a defense because the Steelers' offense also at times has been unmovable.

The team's 347 points scored were their fewest in five seasons and ranked 20th in the NFL. They ranked 22nd in total yards on offense, and none of the 10 ranked below them made the playoffs.

Relief could be on the way in the form of the San Diego Chargers' defense, which ranked 25th in the NFL in yards allowed and 31st in passing yards allowed.

Yet, their Nov. 16 game against San Diego at Heinz Field ranked among their most frustrating on offense this season. Frustrating because it was one of only two games in which they did not score a touchdown, yet their 410 yards were their second-most of the season and it was one of three games in which they had no turnovers.

The Steelers introduced their bend-but-don't score offense that day in an 11-10 victory against San Diego. Jeff Reed kicked three field goals and James Harrison ravaged quarterback Philip Rivers for a two-point sack.

One thing's for sure, coach Mike Tomlin said yesterday, they will need to be more competent near the goal line Sunday.

"There's no hocus-pocus or secret formula for getting the ball in the end zone," Tomlin declared. "We've got to execute better. We've got to put our guys in better position to capitalize on the field position. Those are some of the things we're working on as a staff right now. And those are some of the things we'll work on later in the week with the players."

The Steelers had a chance to score a touchdown in the first quarter Nov. 16 but failed after having a first down at the 8. Willie Parker gained 4, Ben Roethlisberger was sacked back to the 8, and, after a 7-yard pass completion to Nate Washington, they lined up at the 1 on fourth down. Mewelde Moore ran off left guard and was met by the Chargers' Brandon Siler and Quentin Jammer for a 1-yard loss.

That prompted a halftime adjustment that remains in place today; Tomlin installed Gary Russell as his third-down back. Twice, Russell converted on third-and-1 in the third quarter against the Chargers, picking up 6 yards on one carry and 4 on the other. Russell had carried once in the three games previous to that one and 17 over the final seven games, scoring on three short runs.

"I think that was the game we discovered Gary Russell as a potential short-yardage and goal-line runner," Tomlin said. "And that's been solid for us. We don't pretend that it's something mystical. We've just got to formulate good plans, call good plays and execute them."

Tomlin called Russell "a one-trick pony. He's down hill. It doesn't matter what play you call for him. It's down hill. That happens to be a positive attribute for those circumstances."

Russell, signed as an undrafted rookie in 2007, is no Bus. But, at 5-11, he is stocky and heavier than his listed 215 pounds.

"Very rarely is he knocked back," Tomlin said. "He's got a nice center of gravity."

The Steelers also reached San Diego's 3 Nov. 16, but they only had time for one play, and Jeff Reed kicked a 21-yard field goal to end the first half. In the fourth quarter, they had a third down at San Diego's 4. After a 10-yard penalty, Reed kicked the winning field goal from 32 yards with 11 seconds left.

Other than tight end Heath Miller, who did not play in that game because of an injury, and the use of Russell, Tomlin said they will not change much else in their short-yardage from that game of nearly two months ago.

"We won't do anything differently this week that we've done in any of the other weeks in preparation for the game. We've just got to let it all come together a little better than it did the last time."