Collins, 28, was hurt during the fourth quarter of Sunday's 30-23 victory over Carolina. He was taken off the field on a stretcher after attempting to bring down Panthers running back Jonathan Stewart.
Collins spent the night in a Charlotte, N.C., hospital.
It's too early to say if he'll need surgery, Packers Coach Mike McCarthy said.
The safety logged 70 tackles and four interceptions last season for Green Bay.
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