Asante Samuel says playing for Bill Belichick and the Patriots was NOT fun ... and he tells TMZ Sports he believes the reason Tom Brady bolted was 'cause he just couldn't take it anymore.
"He probably just got fed up with it at the end of the day," the former New England cornerback says.
Samuel played with Brady and Belichick from 2003 to 2007 ... and he had a TON of success -- but he tells us he had ZERO fun along the way.
"It worked out for me, man. It made me a better man, but it's not something I enjoyed," Samuel says.
As for why Samuel says playing for The Hoodie is a grind ... it's because of the coach's strict rules and no-mercy personnel decisions.
In fact, Samuel says it was so tough ... he believes that's why Brady will head into the 2020 NFL season with a Buccaneers jersey on.
"He probably just got tired of it," Samuel says of TB12. "He probably got tired of some inner-circle things that he wanted. Maybe, he wanted receivers and tight ends to stay there with him and maybe Bill tried to trade them. Who knows what happened?"
Don't get it twisted, though ... Samuel still seems to respect the hell out of what Bill did for his career -- telling us he just didn't love the route it took to get there.
By the way, Asante -- who's from Ft. Lauderdale -- says he's got a Florida-themed gift for Tom as soon as COVID-19 lockdowns end ... and it's a pretty hilarious present!!