We don't need to speculate anymore. Tom Brady is telling us himself why he left the New England Patriots after 20 seasons.
Brady repeatedly thanked his former teammates and Patriots fans for their support over the last two decades.
But the 42-year-old quarterback also drove home another point: He left New England because he wanted a new challenge.
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"Choosing to leave New England, and the only team I’ve known for 20 years, to join a new football team is a great opportunity, a great change and a great challenge," Brady wrote.
" ... When you play for one team for two decades, change is exciting."
ESPN's Ian O'Connor reported recently that Brady simply had had enough of Patriots head coach Bill Belichick. Our Tom E. Curran also reported that Belichick didn't exactly make Brady feel wanted as the six-time Super Bowl champion entered free agency for the first time.
Brady obviously didn't spell that out, but he did cite a desire to prove (to Belichick, perhaps?) he can still play at a high level.
"Physically, I’m as capable of doing my job as I’ve ever been. Now I want to see what more I can do. I want to see how great I can be," Brady wrote.
" ... I’m excited to be embraced fully for what I can bring to the Bucs. In turn I’m ready to embrace fully a team that is confident in what I do — and what I bring — and is willing to go on this ride with me."
It sounds like Brady's former employer wasn't willing to go on that ride with a QB who turns 43 in August.
Brady indeed will have a much different experience in Tampa Bay under player-friendly head coach Bruce Arians. That drastic change will force Brady to adapt after 20 years with Belichick, but apparently it's a challenge he's eager to tackle.
"It will be a learning curve," Brady wrote. " ... Still, I’m excited. Most of all, I’m motivated. I want to deliver for my new team, my new coaches and my new teammates.
"I don’t want to let anyone down. I’m going to give it everything I’ve got."