Bills linebacker Kawika Mitchell has resumed practicing with the team for the first time since October. Mitchell is recovering from a knee injury and didn't figure he'd be back on the field for another three weeks before taking part in four of five voluntary minicamp practices this weekend. "The way I see it, I'm basically in the biggest dogfight I've been in my whole career," Mitchell said Sunday. "I've accepted that. It's my situation that I'm in." Buffalo is introducing a 3-4 defensive scheme and Mitchell has to learn a new role.