NFL -- Tom Brady Destroyed Cell Phone ... Suspension Upheld

Tom Brady told the NFL he could not submit his cell phone as evidence in the Deflategate investigation because he destroyed it ... this according to the NFL.

The league just issued a statement saying it would UPHOLD Brady's 4 game suspension -- without pay -- for cheating by instructing staffers to deflate the balls in the AFC Championship game.

Brady allegedly texted clubhouse attendants about the plan to deflate the balls -- but when asked for his cell phone, Brady's attorney told the league it was "unavailable because it had been destroyed."

Brady's lawyer told the league, "Text messages exchanged on that cellphone could not be retrieved."

The NFL says, "At the hearing, Mr. Brady testified that it is his practice to destroy (or to give to his assistant to destroy) his cellphone and SIM cards when he gets a new cell phone."

The NFL says Brady gave his old cell phone to his assistant to be destroyed on March 6, 2015 -- the very same day he met with Ted Wells and his team to be questioned about the tampering allegations.

The league says Brady gave them a letter from his cell phone carrier saying the text messages could no longer be recovered.