Brady, 42, was drafted in the sixth round by the Patriots in 2000 and went on to establish a dominant legacy as arguably the greatest of all time.
Together with Bill Belichick he built the Patriots into one of the powerful franchises in the whole of sport, winning the MVP award three times.
However in the past couple of seasons there had been speculation as to the relationship between Brady and Belichick and recently the veteran confirmed that he would leave and explore free agency.
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He has now confirmed that he has signed with the NFC South Bucs.
"Excited, humble and hungry..." Brady wrote on Instagram.
"If there is one thing I have learned about football, it’s that nobody cares what you did last year or the year before that...you earn the trust and respect of those around through your commitment every single day.
I’m starting a new football journey and thankful for the Buccaneers for giving me an opportunity to do what I love to do. I look forward to meeting all my new teammates and coaches and proving to them that they can believe and trust in me...
"I have always believed that well done is better than well said, so I’m not gonna say much more - I’m just gonna get to work! #Year1 p.s. Jack Brady with the photocred 😀"
General manager Jason Licht highlighted Brady's leadership as a key component for the team making the move.
"Tom is a proven champion who has achieved greatness on the field because he demands the best out of himself and his teammates," said Licht in a statement on the team website.
"I've known Tom since we drafted him in New England 20 years ago and through this process it became very clear that his desire to be a champion burns as strong today as it ever has. He possesses the type of rare natural leadership qualities that will immediately impact our entire organization."
Head coach Bruce Arians added: "Tom is the most successful quarterback in the history of our league, but what makes him so special is his ability to make those around him better.
"I have had the privilege to work with some of the best passers in our game, and the characteristics they all possessed were the ability to lead and get the best out of their teammates. Tom is no different.
"He is a proven winner who will provide the leadership, accountability and work ethic necessary to lead us to our goal of winning another championship."
Watching Brady in a uniform that isn't that of the Patriots is going to be very, very weird.
It's also going to be absolutely fascinating to see if he can cope away from Belichick and offensive coordinator Josh McDaniels.
The big plus for Brady is the incredible receiving core at his disposal now with Mike Evans, Chris Godwin and OJ Howard all on the roster.
However the Bucs offensive line is suspect at best and he doesn't have an obvious running back in Tampa.
Brady loves the shorter passing options, not something that Godwin, and in particular Evans are known for.
It will be interesting to see whether or not the Bucs explore slot and running back options in the draft and free agency.
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