Carolina Panthers linebacker Thomas Davis is sceptical over suggestions Denver Broncos quarterback Peyton Manning has suffered a loss of strength in his right arm.

A neck injury and subsequent operations cost Manning a season in 2011 and ended a 14-year spell with the Indianapolis Colts.

The 39-year-old joined the Broncos in 2012 and, after inspiring them to Super Bowl XLVIII in February 2014, his performances this season have been far less impressive - he threw just nine touchdown passes and had 17 interceptions during the regular season.

He was benched in a loss to the Kansas City Chiefs and then missed six games with a torn plantar fascia, but Davis does not believe he has suffered a loss of talent.

"You just don't lose that overnight," the Panthers linebacker said. "Some people are talking about his arm strength, but in the [New England] Patriots game, he looked pretty good to me," he added, referring to the Broncos' win in the AFC Championship game last weekend.

"He's a true competitor and is a guy who's going to come in and do whatever he can do make sure his team leaves the field victorious.

"We have to make sure we're doing everything in our power to make sure that doesn't happen."

Panthers coach Ron Rivera meanwhile described Manning as a "cerebral" player because of his ability to anticipate and pick apart the opposition.

"He's going to know you. He's going to understand you. He's going to attack you the best way he knows," Rivera said.

"He's going to anticipate and do things based on what he sees. You've got to be good at what you do if you're holding your disguise. He wants to undress the defense as quick as possible. It really is a great chess match."

Panthers linebacker Luke Kuechly added he was in no doubt Manning remains a top player: "He's still Peyton. He can still make all the throws. He's throwing outside breaking routes.

"He's throwing balls down the field on seams. He's still got all the throws. I don't care what anybody else says, he's still Peyton Manning."

Manning is currently under investigation by the NFL due to allegations he was sent human growth hormone (HGH).