The 49ers officially opened the practice window for linebacker NaVorro Bowman and three other players on Tuesday, according to Pro Football Talk. Bowman, along with tight end Garrett Celek, offensive lineman Brandon Thomas and cornerback Keith Reaser will have three weeks to be added to the 53-man active roster or their seasons will be lost.
An earlier report had Bowman in danger of missing the remainder of the season due to a torn ACL and MCL in his left knee that he suffered during last season's NFC Championship game. He's expected to be a limited participant in practice all week leading up to Week 12 against Washington.