We already knew that Panthers quarterback Cam Newton would not be playing in Carolina’s Week 4 game against the Texans in Houston. Without going too much into the specifics of Newton’s injury — it reportedly was thought to be a mid-foot sprain — Panthers Coach Ron Rivera made that announcement on Monday, saying there was no timetable for his quarterback’s return.

There might be a timetable now, and it’s not good for the Panthers or Newton.

On Tuesday morning, the Athletic’s Joe Person reported and the NFL Network’s Tom Pelissero confirmed that Newton is believed to be dealing with a Lisfranc injury in his foot, a much more significant injury that involves broken mid-foot bones or torn ligaments — or both — and is often mistaken for a simple sprain. Such injuries often take months to heal and may require surgery, meaning the Panthers will move forward with Kyle Allen as their quarterback for the foreseeable future.

Pelissero reports that the Panthers hope to avoid surgery and will stick with a plan that involves rehabilitation. Such an option is only possible if there are no broken bones or torn ligaments. According to Cedars-Sinai, “it is very important not to put weight on your foot during the initial healing period” and patients must wear a non-weight-bearing cast or boot for six weeks after the initial diagnosis.

In 2013, Redskins safety Phillip Thomas missed his entire rookie season after suffering a Lisfranc injury during the team’s preseason opener (he would return to play eight games for Washington in 2014 before being waived; he has not played in the NFL since). In 2017, Redskins defensive tackle Jonathan Allen suffered a Lisfranc injury during a game in October and missed the rest of the season (however, he returned in 2018 and started 17 straight games for the Redskins).

According to Lower Extremity Review magazine, 28 NFL players suffered Lisfranc injuries between 2000 and 2010. Only two never returned to competition. But the median time to return was 11.1 months from the time of injury, and only three players returned in less than three months.

Making his second career start Sunday against the Cardinals, Kyle Allen completed 19 of 26 passes for 261 yards and four touchdowns as Carolina won for the first time this season. According to ESPN Stats and Info, Allen’s 90.6 QBR is the highest by any quarterback in his first two career starts.

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