The six-time All-Pro middle linebacker will be back on the field Sunday as his team tries to derail Green Bay for the third time in a calendar year. He fractured his right hand going against fullback Bruce Miller in a blitz-pickup drill during training camp July 31.
"It's doing good, healing well," Willis said Wednesday.
"You play this game you endure a lot of pain. It's one of those things when you try to shake it off usually my body would just absorb the pain...but my body's not taking it, so I knew then it was worse than just a bump."
Jim Harbaugh didn't indicate any concerns regarding Willis' hand and any lingering effects. Willis is still deciding what kind of brace, cast or wrap will be on his hand Sunday afternoon.
The bone isn't completely healed, Willis said. That process could take up to eight weeks. This Friday will mark exactly five weeks since his surgery.
"The doctor said it looks good, so that's the big thing," he said.
The 49ers face the challenge of a Packers offense looking to establish more balance with a running game headed by rookie Eddie Lacy. The former member of the Alabama Crimson Tide was taking in the second round by Green Bay as the team hopes to fortify its running attack.
The Packers finished last season ranked No. 22 in the NFL averaging 104.6 yards per game on the ground, despite having the fourth-highest scoring offense in football.
Willis will help anchor San Francisco's defense that finished third against the rush in 2012.
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