Jennings (undisclosed) was placed on injured reserve Thursday.
Jennings will miss the entire season as a result of his placement on IR. He had been the favorite to secure the third spot on New England's running back depth chart behind Rhamondre Stevenson and TreVeyon Henderson. That spot will now go to one of Lan Larison, Jam Miller, Hassan Haskins or the newly signed JaMycal Hasty, unless the Patriots add another backfield option.