“They ask my advice, I tell them, and then they don’t take it.”

Joe Montana says Tom Brady told him that was a real issue in New England … and Joe Cool believes it’s one of the biggest reasons why TB12 is no longer a Patriot.

“I think that was one of his beefs up there,” Montana told USA Today Sports on Wednesday … “I think he would like a little bit of input.”

Joe said in another interview Wednesday with SportsMap Radio that Brady broke it all down for him when the two were at NFL 100 ceremonies at the Super Bowl in February.

“I don’t think he was happy with the way things were progressing there and his ability to have input,” Montana said.

Of course, Brady has never publicly explained what made him leave New England for Tampa … but it’s clear, Montana believes if Bill Belichick had given the QB more say in the offense, he might still be a Patriot.

Regardless, Joe says he thinks Bruce Arians and Co. will be more than willing to give Brady a big role in play-calling and game-planning down in Florida.

“I think they’ll probably let him have that,” Montana said, “especially with the success that he’s had.”

By the way, appears Brady’s loving it in a Bucs jersey so far … he posted some pics of him a Tampa uniform Thursday and wrote, “Dear mom & dad, summer camp is off to a great start.”