The former coach and the G.O.A.T. did not talk at the ceremony where Brady was honored last fall, Tom Brady Sr. said

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Tom Brady’s dad says that Bill Belichick’s gruff manner was not always appreciated throughout his 24 seasons as head coach of the New England Patriots.

“Bill is tough,” Tom Brady Sr. told The Boston Globe. “He runs a military system. It’s a different generation. Bill is a great, great, great coach. But his interpersonal skills are horrible. That’s the bottom line.”

Belichick, 71, who parted ways with the franchise last month after nearly a quarter of a century and six Super Bowl rings, told reporters at his departing press conference that he would “always be a Patriot.”

But during his coaching tenure, the fifth-longest in NFL history, Belichick’s personality often proved hard for players to tackle.

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“Ego sometimes gets in the way of things,” Brady Sr. said. “I think it did with Bill. Now, he’s in a situation where he’s gotten crucified for the last few years by everybody and a lot of luster has come off his rose.”

The former Patriots coach has not yet been hired by another NFL team.

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When the younger Brady, 46, returned to Foxborough in September to be honored at halftime during the game against the Philadelphia Eagles, Brady had a chance to thank the fans who cheered him on for 20 seasons as the team retired his jersey number 12.

It was at that ceremony that Brady Sr. said Patriots owner Robert Kraft admitted that the team made a mistake when it let the G.O.A.T. leave for Tampa Bay.

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“He just said, ‘I made a mistake.’ He told us that back in September,” Brady Sr. said of Kraft. “We don’t all make the right decisions, but he’s made a hell of a lot of good ones over the years.”

The head coach and the retired quarterback did not interact at the ceremony, Brady Sr. said, and he added that he doesn’t know whether the two have any relationship currently.

“But I know that it galls him that Tommy went elsewhere and won,” Brady Sr. said. “Not that he won, but that he won after Bill said he was done.”

Yet the former athlete seemingly holds his former coach in high esteem.

“He’s the best coach, in my belief, in the history of the game, so I don’t know,” Brady said in November, before Belichick announced his departure, on The Stephen A. Smith Show. “The thought of him not being in New England is hard for me to think about.”