Well this was sudden.
New England Pro Bowl DT VInce Wilfork has asked the team to release him according to Ian Rapoport:
#Patriots Pro Bowl DT Vince Wilfork has asked that the team release him after 10 seasons in New England, according to sources.
— Ian Rapoport (@RapSheet) March 13, 2014
It sounds like he asked for a release because the team wanted him to restructure his deal. He refused to do it.
It will be interesting to see his market coming off an injury.