Ravens C Matt Birk is retiring from football.
He'll make the announcement on Friday. Birk, 36, will go out on top as a Super Bowl-winning center and 16-game starter for the Ravens. A Harvard alum and the 2011 Walter Payton NFL Man of the Year, Birk earned six Pro Bowl trips -- all with Minnesota in the 2000s. He continued to play at a very high level into his mid-30s and had gas left in the tank even as he retired. For bookkeeping purposes, Birk's retirement "saves" the Ravens $2.05 million in salary cap space. It also creates yet another needy spot on GM Ozzie Newsome's roster.