The agent of New England Patriots' Tom Brady has called the appeal process of the quarterback's suspension for the deflategate scandal a "sham".

The 37-year-old's four-game ban was upheld by league commissioner Roger Goodell after it was revealed that Brady was unable to provide evidence to contradict the findings of the report by Ted Wells into the incident in his hearing in June.

However, Brady's agent Don Yee has blasted the process, insisting that his client was not given a fair appeal and that he and the Patriots are completely innocent of any wrongdoing.

Yee said in a statement: "The commissioner's decision is deeply disappointing, but not surprising because the appeal process was thoroughly lacking in procedural fairness. Most importantly, neither Tom nor the Patriots did anything wrong. And the NFL has no evidence that anything inappropriate occurred.

"The appeal process was a sham, resulting in the commissioner rubber-stamping his own decision. For example, the Wells investigative team was given over 100 days to conduct its investigation. Just days prior to the appeal hearing, we were notified that we would only have four hours to present a defense; therefore, we didn't have enough time to examine important witnesses.

"The commissioner's decision and discipline has no precedent in all of NFL history. His decision alters the competitive balance of the upcoming season. The decision is wrong and has no basis, and it diminishes the integrity of the game."

Brady has reportedly given his authorisation to the NFL Players Association to take his case against the NFL to federal court.