Carolina Panthers quarterback Cam Newton’s rehabilitation from an injured foot is not going well. On Friday, he traveled to Green Bay, Wis., to visit foot specialist and former Carolina assistant team physician Robert Anderson, the team announced.

Newton played in Carolina’s first two games this season before the team shut him down because of the injury, which he originally suffered in the preseason. But he was seen jogging lightly and throwing before the Panthers’ road loss to the 49ers on Sunday (he also traveled with the team for the first time since the injury, which was seen as a positive step in his rehab). But on Friday, the NFL Network’s Ian Rapoport said Newton’s condition “is not getting better” and that he’s visiting Anderson to find out why.

“Playing football is a long way off,” Rapoport says.

The Panthers are 4-1 with Kyle Allen starting at quarterback in place of Newton, but Allen struggled in Sunday’s loss to San Francisco, throwing three interceptions (the first of his NFL career) and taking seven sacks. Carolina hosts Tennessee on Sunday.

Panthers Coach Ron Rivera has said Newton will assume the starting job when healthy, but a report surfaced last month saying Carolina feels Allen has a better chance of staying healthy than Newton, who also missed the tail end of last season with a shoulder problem that required surgery. Newton has a $21 million salary cap hit next season, the final year of his contract.

“I spent a long time speaking with Cam this week and he’s done everything he possibly can in his rehab process to get his foot to 100 percent,” Panthers General Manager Marty Hurney said in a story on the team’s website. “Unfortunately, we haven’t reached that point. The next step is for him to go see Dr. Anderson and gather more information.”

Lisfranc injuries, which involve broken mid-foot bones or torn ligaments, can take months to heal and may require surgery, which might be the next step in Newton’s recovery.

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