Count Joe Montana in the group stunned that it happened: Tom Brady left the Patriots.

“I don’t know what’s going on inside there, but somebody made a mistake,” Montana told USA TODAY Sports, pondering Brady’s huge free agent move to the Tampa Bay Buccaneers.

Montana, who similarly shook up the NFL landscape a generation ago when the 49ers traded him to Kansas City in the latter stage of his career, knows the backstory. Brady, 42, obviously wanted out – or at least the option to go – and forced his way onto the market with a clause in his final New England contract that prevented the team from using a franchise tag to keep him.

Yet there’s lingering intrigue as to why the NFL’s most decorated quarterback looked to bolt.

“I think when you look at the whole situation, you try to figure out how you want to get away from things that are there,” Montana, 63, said from his Northern California home during a phone interview. “I had a different story, where they had made a decision. He, obviously, they never would have gotten rid of. I still don’t understand how New England let him get away. I don’t understand that.”

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But Montana – who happened to be one of Brady’s football idols while the future three-time MVP was growing up in the San Francisco Bay Area – can surely connect the dots with a few clues. While Patriots owner Robert Kraft has insisted he tried to convince Brady to stay – and Brady expressed love, respect and gratitude for Kraft, Bill Belichick and the franchise -- the Hall of Fame legend talked to the former New England star briefly at Super Bowl LIV and got a sense of what may have driven the departure.

“It’s not about appreciation,” Montana said, dismissing one of the prevailing theories. “He wants control. I mean, he wants a lot of control. I don’t know what Tampa Bay gave him, but at some point in time, you’re just a player. You can try to get what you can and do what you want, but in the end, you’re still not in the hierarchy when it comes to hiring people, firing people and all that.

"I don’t know exactly what he’s looking for, but my understanding was that he’s just looking for more control of the offense. But I don’t know. I haven’t had a long conversation with him; I talked to him a little bit at the Super Bowl, but not enough time to really get in-depth.”

There may be no person in the NFL universe other than Montana who can relate to Brady as he embarks on his late-chapter journey with the Bucs. Sure, the league that Brady has thrived in while winning a record six Super Bowl championships has evolved from the game that Montana often dominated. Yet there’s a parallel in that they are both ultimate winners. Until Brady came along, Montana and Terry Bradshaw were the only quarterbacks to win four Super Bowls – and “Joe Cool” never threw an interception on the title-game stage. He also senses how invigorating it must be for Brady to transition to a new franchise hoping to parlay his winning pedigree into its own championship moment.

“What he wants is a bit more weapons,” Montana said, mindful that the Bucs are loaded with arguably the NFL’s best tandem of wide receivers in Mike Evans and Chris Godwin. “But more weapons doesn’t always mean you’re going to continue to win. There were times we had a lot of weapons later in my career, but we had up and down years; Steve (Young) had up and down years with the same group. That’s not always the case that happens with it.

“I mean, you can go back at look at the Super Bowls that (the Patriots) won. They won a lot of close ones, but it’s still about the people, how they fit into that offensive system, how they’re doing in understanding each other. You go back and people probably can’t even remember my first two groups of receivers in those first two Super Bowls, other than Dwight (Clark).

"Sometimes you’ve got to be careful of what you wish for. Sometimes you get it and it becomes a little more pressure if they don’t perform. Those guys have put up some big numbers, but in a different style of offense. It’ll be interesting to see what they mix in with what they did in New England with what they’re going to do and continue to use and had success with in Tampa.”

Montana believes that Bucs coach Bruce Arians, along with coordinator Byron Leftwich and consulting guru Tom Moore, will need to tailor the offense to accommodate Brady, which will result on less reliance on the deep passing game. Arians’ “no risk it, no biscuit” philosophy can generate chunk plays downfield by the big-play receivers, but it also increases the risk on quarterbacks standing in the pocket while opportunities develop.

“We’ll see,” Montana said. “He’ll be a good addition to that team, as long as they don’t hold the ball like they’ve been doing. I don’t think he fits into that category to hold the ball. Can he do it? Yeah. But physically, it becomes a different game when you’ve got to hang on, because you’re going to get hit. What they do in New England, they get the ball out of their hand pretty fast. Occasionally, they’ll throw it downfield. They probably have a little better offensive line (in Tampa) than in New England.”

During an introductory conference call on Tuesday, Brady maintained that his priority will be to find the open receiver, regardless of where on the field the opportunity exists.

With the New England days in the past, Montana thinks Brady will draw on his determination to prove that, even without Bill Belichick, he can still be the difference-making quarterback he was in reaching nine Super Bowls during 20 years with the Patriots.

“I think it’s going to be fun for him,” Montana said. “Probably for the first time in a long time he’ll be having fun, if I understand what he’s been saying, or what I’ve been reading.”

Montana, who played just one game in his final two seasons in San Francisco amid elbow surgery, lasted two years with the Chiefs. He was never able to duplicate his Super Bowl success with his new team, but he led Kansas City to its first division crown in 22 years and an AFC title game appearance. In his final season in 1994, the Chiefs were eliminated in the wild-card round.

Asked how his Kansas City transition relates to Brady’s new situation, Montana said: “It actually brings a new excitement to you, to a certain degree. Because it’s not going to be the same-ol', same-ol' going into the same locker room that you’ve been going into for so many years, seeing the same people over and over. He doesn’t need a fresh start, but it gives you a great feeling inside, looking forward to trying to help the team move forward. And everybody believes in him, looking forward to watching him play.”

Montana knows that chemistry will be essential for Brady to develop.

“It’s just getting used to your new teammates,” he said. “Everybody knows what you’ve accomplished, but it’s always about, ‘What can you do for me now?’ “

That’s not to be confused with any type of overwhelming pressure.

“No one will put more pressure on him to perform than himself,” Montana said. “That’s his makeup. Most players who have been that successful have that makeup that you can’t add pressure to him. Outside pressure, that external pressure, it slips off your back. I think the pressure comes from within, wanting to perform and show that he can make that change.”

When Montana left the 49ers, traded by then-team president Carmen Policy, it was the ultimate reality check. The titles didn’t matter. The franchise chose to move forward with Young.

“They say it and it comes up all the time, but it becomes a business," Montana said. "At some point, it’s business. That’s why I had long talks with (Hall of Fame former 49ers coach) Bill (Walsh) about our relationship, after he retired. The relationship that happens, everybody makes it look like there’s friction, but in the end, he goes, ‘I just had to keep my distance to a certain point from you because I can’t become your best friend. Because I have to make a decision on you at some point.’ Although Bill didn’t make the decision, and I don’t think he would have made the same one that was made.”

Montana played his final game with the 49ers in the 1992 regular-season finale, coming off the bench after missing nearly two full seasons to play the entire second half of a Monday night victory against the Lions. In the stands that night at Candlestick Park: Brady.

On Tuesday, Brady wistfully recalled his affection for Montana and how he would throw footballs in the parking lot at Candlestick Park before 49ers games.

Told of Brady’s remarks, Montana giggled.

“That just means that you’re old,” he said.

But he can still relate.

Follow USA TODAY Sports' Jarrett Bell on Twitter @JarrettBell.

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