Steelers face 49ers in a battle of 10-3 teams

The Pittsburgh Steelers would like to move from wild-card leader to the top-seeded team in the AFC during the NFL’s final weeks.

Take away quarterback Ben Roethlisberger and linebacker James Harrison on Monday night at NFC West-leading San Francisco, and that pursuit gets more difficult.

Roethlisberger was kept out of full practices last week after spraining his left ankle in a 14-3 victory over the Cleveland Browns on Dec. 8, and Coach Mike Tomlin said the quarterback with two Super Bowl rings is “day-to-day” with the pain.

The Steelers (10-3) are trying to leapfrog Baltimore (10-3 before Sunday night) as NFC North leader. Pittsburgh has defeated AFC East leader New England (11-3) this season, but it lost to AFC South-leading Houston (10-4).

Tomlin said Roethlisberger, with 3,526 yards passing and 21 touchdowns this season, is not required to take a slew of practice snaps in order to play. He left a practice Wednesday limping.

If Roethlisberger is out in the matchup of franchises with 11 combined Super Bowl titles, the Steelers can use either veteran Charlie Batch or the more mobile Dennis Dixon against the league’s top rushing and No. 4 overall defense.

The 49ers (10-3) are 6-1 at Candlestick Park and chasing the No. 2 seeding, which comes with a first-round playoff bye, in the NFC. San Francisco holds a slight edge over New Orleans for the spot based on its conference record.

49ers quarterback Alex Smith will face the league’s No. 2 defense.

If there’s any solace as he returns from his worst game of the season (18 of 37 for 175 yards and no touchdowns in a loss at Arizona), Smith will avoid Harrison, the fierce pass rusher who has been suspended for the game after delivering a helmet-to-helmet hit on Cleveland quarterback Colt McCoy last week.

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