The Patriots have lost another piece of a defense that has lost several this season.

Linebacker Brandon Copeland, per a source with knowledge of the situation, is telling teammates that he suffered a torn pectoral muscle on Sunday against the 49ers.

Copeland has started four games this season, his first with the Patriots. Undrafted in 2013, he has played for the Lions and Jets, after offseason/preseason stints with the Ravens and Titans.