After losing Will Svitek for all of 2012 before the season even started, this is another huge blow. Grimes left the game on Sunday in the fourth quarter with what was initially reported as a calf injury. Now we know the seriousness of what transpired in Kansas City.
Asante Samuel will move into Grimes' spot now, making that offseason acquisition so much more important now. Dominique Franks and Christopher Owens will battle for the nickel.
The Falcons started off with a big win over the Chiefs, but this puts a damper on the revelry afterwards. We'll await the rest of the story from Atlanta, but for now we know a huge piece on defense will be missing going forward.