"Personally, I feel just terrible. It was a very unusual injury," McCarthy said after a short hour and a half practice Saturday night. "If you have a chance to see it on film, it's just unfortunate. Everyone knows the type of player Desmond is for us. He's definitely one of the spiritual type of individuals.  The energy he brings to the workplace and just the way he plays. He puts so much into it. After last year with his calf injuries, I know he was really looking forward to having a big year."

Bishop is coming off a career-best 142 tackles and five sacks in 2011 despite missing three games with calf injuries.

D.J. Smith will replace Bishop in the middle of the Packers 3-4 defense next to A.J. Hawk.  Smith was impressive replacing Bishop last year and says he's ready for the opportunity.

"As a professional you've got to stay ready," Smith said Saturday before practice.  "It's always a next man up league and you have to be prepared when your name is called. Taking those reps when Bishop was down earlier in camp with the one's really helped out a lot so I was ready to go."