New York: Tom Brady’s four-match ban over the “Deflate-gate” scandal was upheld on Tuesday as it emerged the New England Patriots star had ordered the destruction of a cellphone containing potentially crucial evidence.

In a bombshell ruling, which followed speculation that Brady’s ban would be slashed or even cancelled, National Football League commissioner Roger Goodell said the original punishment would stand.

Brady, one of the most high-profile athletes in American sport, had been suspended in May after an inquiry found he was at least “generally aware” of a plot by Patriots staff to tamper with the air pressure of balls used during the AFC Championship game against the Indianapolis Colts earlier this year.

The four-time Super Bowl champion quarterback had angrily rejected wrongdoing and appealed against the suspension.

However Goodell dismissed the 37-year-old icon’s appeal in a 20-page ruling.

“I find that, with respect to the game balls used in the AFC Championship Game and the subsequent investigation, Mr. Brady engaged in conduct detrimental to the integrity of, and public confidence in, the game of professional football,” Goodell said. “The four-game suspension is confirmed.”

Goodell said during the course of the appeal it had emerged that Brady had destroyed a cellphone which contained messages and records of his communications with Patriots staff implicated in the scandal.

Brady ordered the destruction of the phone on the day he was interviewed by Ted Wells, the lawyer appointed by the NFL to carry out an investigation into the scandal.

“The most significant new information that emerged in connection with the appeal was evidence that on or about March 6, 2015 - the very day that he was interviewed by Mr Wells and his investigative team - Mr. Brady instructed his assistant to destroy the cellphone that he had been using since early November 2014,” Goodell wrote.

“At the time that he arranged for its destruction, Mr. Brady knew that Mr Wells and his team had requested information from that cellphone in connection with their investigation.”

Goodell wrote that the destruction of the phone, which had been used to send some 10,000 messages between November 2014 and early March, was only revealed on the day of Brady’s appeal hearing on June 18.