If Callahan indeed out for year with broken foot, it’s a tough development for breakthrough player. Will hurt pass rush —he’s an excellent blitzer—and coverage in nickel vs. physical slot WRs. McManis is a quality sub but Callahan was like 12th starter on elite D.
If Callahan can return at any point, that's excellent news. I mean one more win and you're simply playing for the No. 3 vs No. 4 seed anyway.