CHARLOTTE, N.C. (AP) — Panthers coach Ron Rivera says he expects injured quarterback Cam Newton to return to practice "pretty soon," without giving a timetable.

Rivera remains "cautiously optimistic" that Newton, who remains in a walking boot, will be ready for the Sept. 8 regular season opener against the Los Angeles Rams.

Newton sustained a left mid-foot sprain in Carolina's 10-3 loss to New England on Thursday night. Rivera expressed relief the injury wasn't worse, saying "very much so — he's our starting quarterback."

Newton was inside the stadium receiving medical treatment while the team practiced on Saturday. Rivera says trainers want Newton to stay off the foot and keep it elevated as much as possible.

Newton hasn't spoken to the media since the injury.

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