SAN FRANCISCO The Cardinals were driving. The 49ers' defenders were hurting. And the momentum in the game was shifting to Arizona.
That's when Patrick Willis turned to NaVorro Bowman. One of us needs to make a play, one inside linebacker said to the other. And with the 49ers leading by just two points late in the third quarter Sunday at Candlestick Park, one did.
As Cardinals wide receiver Larry Fitzgerald was going to the ground after a short reception at the San Francisco 23-yard line, Willis jammed his hand into Fitzgerald's midsection and knocked the ball free. The turnover set up an 18-play drive that ended with a short Kendall Hunter touchdown run that seemed to squeeze the life from a Cardinals team that threatened to take the lead just a few minutes earlier.
The 49ers won 32-20 and now stand alone in second place in the NFC West, one game behind the Seahawks.
Rookie safety Eric Reid and cornerback Carlos Rogers intercepted Carson Palmer passes in the first quarter. Outside linebacker Corey Lemonier sacked Palmer for a safety in the second quarter, then forced another fumble in the fourth quarter. But it was Willis' takeaway, his teammates said, that changed the course of the game.
"Huge," said defensive end Justin Smith. "They were driving. We were needing a stop, and Pat came up with a turnover. That was the catalyst of the game right there."
"Just the right time," safety Donte Whitner said. " It was a big play in the football game. You never know what play is going to change the momentum of the game."
In preparing for the Cardinals, Whitner said the 49ers noticed that Fitzgerald, who had a 75-yard touchdown in the first quarter, carried the ball a little loosely when he ran, and they knew there would be an opportunity to force a fumble.
Willis did so with his left hand. The right one, he said, still is recovering from a fracture suffered at the start of training camp. He also was hampered by a groin injury that kept him out of the two previous games, and he admitted he wasn't at full speed in his first game back.
"I was telling NaVorro I feel like a rookie again," Willis said. "My eyes aren't where I wanted them to be. But we got the win."
Playing injured has become a theme for the 49ers' defense.
Defensive end Ray McDonald endured the game with a torn biceps tendon, and he said his right arm was not at full strength. After losing starting nose tackle Ian Williams to a broken ankle in Week 2, the 49ers watched his replacement, Glenn Dorsey, leave Sunday's game with a hamstring injury in the first quarter.
Even Dorsey's backup, Tony Jerod-Eddie, had to go to the sideline for a few snaps after his leg began to cramp.
At one point, both Jerod-Eddie and another reserve lineman, Demarcus Dobbs, were on the sideline getting stretched out by trainers.
"Our players really toughed it out when they had to," said coach Jim Harbaugh, who highlighted the defensive line. " They were hurting, and that bunch of guys just toughed it out."
Harbaugh said fifth-round draft pick Quinton Dial, who is likely to practice with the team for the first time this week, could be in a backup role at nose tackle for Sunday's game at Tennessee.
Defensive coordinator Vic Fangio was more skeptical last week when asked how quickly Dial could contribute, but Dorsey's injury could force the issue.
Willis, meanwhile, said early in the game he was unexpectedly bumped by Fitzgerald between plays. The two are friendly off the field, but Willis didn't like the extracurricular contact, even if there was no malice.
Said Willis: "I told him in the second half, 'I haven't even tackled you yet. I'm going to have to get you; I'm going to have to tackle you at some point.' "
Read Matthew Barrows' blogs at www.sacbee.com/sf49ers and listen for his reports Tuesdays on ESPN Radio 1320.