49ers released C Eric Heitmann. Heitmann failed his physical. It's no surprise considering he was deemed unlikely to play football in 2011 due to neck surgery. Heitmann's career is in doubt and with David Baas now in New York, the Niners are desperate at center.

49ers LT Joe Staley revealed that C Eric Heitmann suffered his career-threatening neck injury in former coach Mike Singletary's infamous "nutcracker" drill. Singletary was the only coach still using the drill, which was more common half a century ago. The nutcracker involves two like-sized players crashing into each other to gain leverage. Patrick Willis (ankle), Tarell Brown (toe), and David Baas (broken foot) also sustained injuries from the drill. Upon installing the nutcracker, Singletary labeled it "pretty foolproof." The players felt differently.

49ers C Eric Heitmann is unlikely to play football in 2011 after undergoing neck surgery recently. It will be Heitmann's second lost season in a row; he missed 2010 with a fractured left fibula and the neck complications. The latest surgery was to repair a ruptured disk in the neck. (Free agent David Baas just got more leverage.) Heitmann's timetable for recovery has been optimistically set at six months. His agent says Heitmann's "hopes are to play as soon as he's cleared."