The Patriots won big on Sunday, but they did lose four players to injuries in the first half.
Langi sprained his medial collateral ligament, Ian Rapoport of NFL Media reports.
The linebacker will undergo further medical testing to determine a prognosis.
He started his first game of the season on Sunday but played only five offensive snaps and seven on special teams before his injury. In seven games, Langi has two tackles. He has seen action on 16 defensive snaps and 98 on special teams.