Joe Staley was admittedly rusty in his return to the field.
No matter, San Francisco's six-time Pro Bowl linebacker made an impact in a 32-20 win over the Arizona Cardinals.
After missing two games with a groin injury, Willis punched out his first forced fumble of the season and 15th of his career. The 49ers linebacker stripped Cardinals wide receiver Larry Fitzgerald which was scooped up by free safety Eric Reid, for the rookie's first-career fumble recovery.
It was Fitzgerald's sixth career fumble (794 receptions in 10 seasons).
Willis put a stop to an Arizona drive where the Cardinals looked to regain the lead, trailing 22-20 late in the third quarter.
"It was just one of those plays where I was just able to get my hand on the ball," Willis explained. "And what was funny was earlier in the game, I have known Larry Fitzgerald for a long time, a good friend, and he kind of bumped me, came out of nowhere and bumped me and I didn't know who it was.
"I was like, 'Wow, he really bumped me.' He was just joking, but he kind of bumped me on purpose. And once I got my chinstrap broke I don't like friends, I have friends after the game. So, 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.' So, it was a good play on the ball and E-Reid did a great job of getting to it and picking it up."
Willis tied teammate Carlos Rogers for the team lead with eight tackles against the Cardinals.
The return of the All-Pro linebacker lifted an already talented defensive unit, one that had been creating turnovers without Willis' services.
The 49ers defense forced 10 turnovers in the last three weeks. With Willis in the lineup, San Francisco recorded four takeaways against Arizona. Over the past three weeks, the 49ers have turned all 10 of their takeaways into points (six touchdowns and four field goals).
Willis was happy to be a part of San Francisco's winning formula once again.
"I think anytime as a defense that you can get turnovers it's huge," the seven-year veteran linebacker said. "I think takeaways take the momentum from the other team and give it to us.
"I know we got some takeaways earlier in the game in which we could have capitalized on, touchdown wise. But we got some points off of them and if we just continue to get those takeaways than it lessens the chance of their offense being able to have the opportunity to score and more for ours. So, we just have to continue to go after the ball and get it."
Willis believes he can play better than his return to action on Sunday. It's a scary thought.
"I have a lot of pride," the 49ers defensive co-captain said. "It's one of those things, you come out today and we let some runs get out on us and some big plays."
Arizona picked up 109 yards on the ground, averaging 5.2 yards per carry.
"I know I take responsibility for some of those run plays," Willis added. "But we got the win and it's one of those things that the more I'm able to get back out there and get back into the game-flow, I feel like I'll get it back."