Newton (undisclosed) did not participate in Tuesday's practice, John Keim of ESPN.com reports.
Newton does not currently have a return timeline. The Commanders signed a defensive tackle to the roster Tuesday morning, meaning the 23-year-old's injury could be significant. The reserve option was likely set to play a significant share of snaps in Saturday's preseason contest with the Lions. If Newton cannot return to the field in time for the game, Shy Tuttle and Ricky Barber could potentially see more opportunities.