One final tough test comes first.
The 49ers take the NFL's third-ranked rushing offense to Arizona on Sunday to face the league's top-ranked rushing defense. They'll do it without regular starter Miller, a key player in San Francisco's run scheme who will miss the rest of the season because of a shoulder injury.
Anthony Dixon and newcomer Will Tukuafu played well in Miller's place Monday night as the 49ers rolled to 199 yards on the ground in a 34-24 victory over Atlanta that clinched a playoff berth.
And with All-Pro left guard Mike Iupati back in the lineup after a four-game absence, San Francisco's running game appears to be peaking at the right time for a team ranked 31st in the NFL in passing offense.
After a November lull when the 49ers rushed for 83 yards or fewer in three consecutive games, San Francisco (11-4) has averaged 183 yards on the ground the past three weeks while building momentum during a five-game winning streak.
"We had a slump there but we all talked about it and said we had to get back on track," halfback Frank Gore said Friday. "We had to get all the grinding yards, all the tough yards, and that's what we're doing now. We attack. Our O-line is doing a great job attacking, I'm attacking, Kendall (Hunter) attacking, so we're ready to play."
Nobody seems more ready than Gore, a four-time Pro Bowl player who's completing another outstanding season as the main man in San Francisco's attack. Gore ranks seventh in the NFL with 1,114 rushing yards —the seventh 1,000-yard season of his nine-year career — and he enters Sunday's game needing 47 yards to reach the 10,000-yard career threshold.
Gore's not the only one closing in on a rushing standard. Colin Kaepernick, who has 500 yards rushing this season, needs 38 against the Cardinals to break Steve Young's franchise record for most rushing yards by a quarterback in a season.
With Hunter (345 yards rushing) complementing Gore with his change-of-pace quickness - Hunter's season-longest 45-yard run set up a short touchdown run by Gore against Atlanta - the 49ers pounded Atlanta on the ground in their first game without Miller, who was injured Dec.15.
Miller was a Pro Bowl alternate for his play in front of Gore last season, but Dixon and Tukuafu both opened holes with their blocking against the Falcons. They combined for 23 snaps and coach Jim Harbaugh said, "They both did very well and we can build on that, add to what each does going forward."
Tukuafu was playing his first game of the season after signing a two-year deal with the team Dec. 18. The 293-pound Tukuafu originally was a defensive lineman who played both positions for the 49ers last season before being released in September.
"If the team was going to bring me in, it was to contribute," Tukuafu said. "I just tried to go in and do my job out there. I wasn't with the guys when they were grinding it out the whole season, but we feel good with the running game, and you have to have that sense of confidence when you're going to make that postseason run."
The 49ers can bolster that confidence with another strong showing against Arizona, which allows a NFL-low 84.5 yards per game on the ground.
The 49ers rushed for 149 yards during their 32-20 win over the Cardinals on Oct. 13 in San Francisco. After Arizona had crept within 22-20 in the third quarter, the 49ers put away that game with an 18-play, 89-yard touchdown drive that featured 11 running plays and lasted more than nine minutes.
"We're going to treat it like a playoff game, and I know they're going to come to play," Gore said. "Their front seven plays great together, they're very physical and run to the ball. But we're built for it, and we're going to be ready."
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