It's one of the many hidden gems in NFL Films' documentary, "Bill Belichick: A Football Life."

During a 2009 Patriots-Ravens game, Baltimore wide receiver Derrick Mason catches a pass near New England's sideline and runs out of bounds near Belichick.

Mason says a few words ... then a mic'd-up Belichick lashes out.

"F--- you Mason," he says. "Why don't we talk after the game, all right? Just shut the f--- up."

So, what prompted Belichick's outburst? In a 1-on-1 interview with our Tom E. Curran on Thursday at Tennessee Titans practice, Mason shared his side of that spat -- and insisted Belichick shouldn't have gotten involved in the first place.

"Here's the thing: None of it was directed at Bill," Mason told Curran. "It all had to do with Dean Pees."

Pees, the Patriots' defensive coordinator at the time, had a history with Mason, as he was on Michigan State's coaching staff (under head coach Nick Saban) while Mason was a Spartan.

And Mason says he was actually trash-talking Pees, not Belichick.

"Dean Pees and I had a relationship. So, Dean Pees and I are going back at each other and I was laughing, because I enjoy having fun on the field," Mason told Curran. "I was laughing, and we were moving the chains. And I guess Bill just took exception to it, and Bill said something, and I laughed it off.

"Dean Pees and I talked about it (afterward), and I was like, 'It was you and I, coach, not him.' "


In Belichick's defense, Mason was running right past the Patriots coach while (supposedly) jawing at Pees, so we can understand the mixup here. And Belichick wasn't exactly in a cheery mood during the 2009 campaign, which ended in a 10-6 record and a Wild Card-round loss to Mason's Ravens.

But Mason would like to clarify that he didn't totally deserve Belichick's earful.

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