Patriots Coach Bill Belichick, meanwhile, refused to answer questions about Brady's suspension, saying that Kraft had already addressed the team's position on the matter.
The decision on Brady's appeal, written by Commissioner Roger Goodell, was made in part because of "important new information" disclosed by the star quarterback and his representatives during the hearing, the NFL said. This includes the June 18 disclosure that Brady had "directed that the cell phone he had used for the prior four months be destroyed" despite investigators' request to access information stored on that device.
"Notwithstanding my enormous respect for his accomplishments on the field and for his contributions and role in the community, 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 wrote.
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In response to the commissioner's decision, Brady authorized the NFL Players Association to appeal his case in federal court, NBC News reported.
On Wednesday, Brady posted on Facebook that he is "disappointed" by the NFL's decision.
"Despite submitting to hours of testimony over the past 6 months, it is disappointing that the Commissioner upheld my suspension based upon a standard that it was 'probable' that I was 'generally aware' of misconduct," Brady wrote. "The fact is that neither I, nor any equipment person, did anything of which we have been accused. He dismissed my hours of testimony and it is disappointing that he found it unreliable."
The Patriots were accused following the AFC championship game in January of intentionally deflating footballs (which many players say makes them easier to throw and catch). The incident was dubbed "deflategate" by some in the media.
"Based on the Wells Report and the evidence presented at the hearing, Commissioner Goodell concluded in his decision that Brady was aware of, and took steps to support, the actions of other team employees to deflate game footballs below the levels called for by the NFL's Official Playing Rules," the NFL statement said.