The reigning NFL MVP was hit by Falcons linebacker Deion Jones as he reached the goal line.Derek Anderson came in for Newton on the ensuing drive and finished the game.
"I saw it was a quarterback run," Jones told ESPN's Ed Werder. "It looked like he let up a little at the goal line, and I just tried to make a good play."
Panthers coach Ron Rivera said Newton "probably" could have avoided the hit.
"I haven't seen it close up, so we'll see it when I get an opportunity to watch tape," Rivera said.
Newton's injury was suffered on a play similar to last year against the New Orleans Saints. On that play,he wasn't evaluated for a concussion until after he completed the drive.
Newton said after that game thathe "let my foot off the gas" and would never let that happen again.
Anderson will start if Newton can't play Oct. 10 against the Tampa Bay Buccaneers. When Newton missed two starts in 2014 -- one with fractured ribs and one with a broken bone in his back from a car wreck -- Anderson went 2-0. Both games were against the Buccaneers.
Anderson finished 17-for-23 for 172 yards and 2 touchdowns in the fourth quarter Sunday. He also threw two interceptions.
"I thought he did some really good things, except for the one he thought he was throwing away [that was intercepted]," Rivera said. "He made some really good reads. He put us in position to score and gave us a chance."
Anderson said he will be ready if called upon.
"If it happens, it happens," Anderson said. "I'll come in and work, and we'll see what happens."
Anderson couldn't say for sure if Newton could have avoided the hit on the two-point conversion.
"I don't think he saw the guy," Anderson said.
But Anderson admitted it reminded him of the New Orleans hit Newton took.
"When I'm running, I'm running as fast as I can until somebody tackles me, because I'm not very fast," Anderson said. "That's how I see it."
The Panthers and the NFL came under fire when Newton wasn't taken out of the their season opener against the Denver Broncos after taking a hard hit to the head that left him on the ground longer than normal.
After the Broncos game, Newton passed three concussion tests, but the league and the NFL Players Association are investigating whether the situation was handled correctly at the time. Rivera said Friday that he had not yet been questioned on the matter.
Newton gets rocked at the goal line, leaves the game with concussion
On a two-point conversion try, Cam Newton gets nailed in the head by Deion Jones at the goal line. The Panthers would get the two points, but Cam Newton would leave the game with a concussion.
Panthers taking Newton's hit very seriously
Ashley Fox breaks down how the Panthers plan to proceed with Cam Newton, who has been placed in concussion protocol after being taken out of a loss to the Falcons following being hit hard on a two-point conversion.