The Denver Broncos will support Peyton Manning "100 per cent" following accusations he was one of a number of athletes supplied with performance-enhancing drugs.
An Al Jazeera documentary claimed human growth hormone (HGH) was mailed to Manning's wife after he underwent neck surgery in 2011.
Manning has since released a statement, labelling the allegations "complete garbage".
And a Broncos statement read: "Knowing Peyton Manning and everything he stands for, the Denver Broncos support him 100 per cent.
"These are false claims made to Al Jazeera, and we don't believe the report.
"Peyton is rightfully outraged by the allegations, which he emphatically denied to our organisation and which have been publicly renounced by the source who initially provided them.
"Throughout his NFL career, particularly during his four seasons with the Broncos, Peyton has shown nothing but respect for the game.
"Our organisation is confident Peyton does things the right way, and we do not find this story to be credible."
Manning's former team, the Indianapolis Colts, also backed their two-time Super Bowl quarterback, branding the report "utterly ridiculous".
A Colts statement read: "Peyton played the game in Indianapolis for 14 years the right way.
"He never took any shortcuts and it would be absurd to suggest he would have taken prohibited performance enhancing drugs.
"We also note that the 'source' of this allegation has since recanted his story. The entire Indianapolis Colts organization and the Irsay family hope this crude effort to besmirch Peyton's reputation will not be permitted to tarnish the legacy of a great Colt."