For the first time during a friendship spanning almost four decades, Alabama coach Nick Saban and New England Patriots coach Bill Belichick allowed cameras to film their annual meeting of two of football’s most accomplished minds.

Conversations between Saban and Belichick, both in Saban’s office and his Tuscaloosa home, were captured last spring for the HBO Sports and NFL Films documentary “Belichick & Saban: The Art of Coaching," which will be released to the public Tuesday at 8 p.m. CT.

Director Ken Rodgers’ goal was to “get out of the way” and allow organic conversation between the two coaches.

At one point, that yielded some commentary from Saban that hinted at some friction between him and former assistants, Georgia coach Kirby Smart and Tennessee coach Jeremy Pruitt.

“We’ve always had sort of a mutual respect for how we sort of take each other’s people,” Saban said to Belichick of their relationship. "It’s one thing that I always try to emphasize to the guys: what I have a tough time with, aight, is we’ve had however many guys who have worked here who are at Georgia, Tennessee -- whoever, wherever -- is when they get those jobs, and in most cases you’ve helped them, is they have a hard time understanding why they can’t take your people.

"I’m gonna help you get a job, [only] so that you can take what I’ve tried to build here and destroy the continuity of what I have? It’s amazing how some of the assistants don’t understand why that’s not a good thing.”

It was unclear which staff members Saban was referencing, but both Smart and Pruitt’s programs include former Alabama assistants. Smart’s co-defensive coordinator at Georgia is former Tide director of player development Glenn Schumann, while Pruitt’s defensive coordinator is Derrick Ansley, who spent a year with the Oakland Raiders before joining Pruitt in Knoxville. Pruitt also hired former Alabama director of player development Kerry Stevenson.

The conversation was framed in the context of Saban, after serving as Belichick’s defensive coordinator with the Browns, not bringing along any of Belichick’s staff from Cleveland upon being hired as Michigan State’s coach in 1995.

“Without really talking about it, we’ve always had that kind of respectful relationship there," Belichick said.

During his first two years after being hired as Patriots coach in 2000, Belichick did bring aboard two of Saban’s former graduate assistants, Brian Daboll and Josh McDaniels, at Michigan State.

“[Belichick] started robbing guys from me,” Saban said in a lighthearted tone during one of his weekly radio shows last month.

But there has been minimal crossover between the two staffs in the nearly two decades since. Daboll spent several years as an assistant for the Patriots and coordinator for three other teams before being re-hired by Saban in 2017 as Alabama’s offensive coordinator. Along with current Patriots special teams coordinator and former Alabama special teams assistant Joe Judge, Daboll is one of only a few coaches to work for both Alabama and the Patriots during the tenures of Belichick and Saban.

Meanwhile, Belichick has seen a number of his staff members hired by his assistants as they have risen to NFL head-coaching jobs elsewhere. Three of his former coordinators -- Houston’s Bill O’Brien, Detroit’s Matt Patricia and Miami’s Brian Flores -- currently hold top NFL jobs and all, to varying extents, have former Patriots staffers working for them.

Belichick, though, has a notably icy relationship with former defensive coordinator Eric Mangini, who became the New York Jets’ coach in 2006. The Patriots filed NFL tampering charges against the Jets that year for an alleged courtship of receiver Deion Branch, and the Jets sparked the “Spygate” scandal in 2007 by tipping off the league to New England’s sideline videotaping practices.

“Look, I’m happy for the people that have worked hard for me to get opportunities," Belichick said in the documentary. “I want to see them build their own program. When they try to tear down our program, that’s kind of where the line, I feel like, gets crossed.”

Saban has also previously expressed an understanding his young coaches could leave the building and rise through the ranks elsewhere.

“Bill does this, and I learned from Bill,” Saban said during his radio show Nov. 14. "He was always looking for those young guys. But he was looking for them so that even if they went someplace else, he had them in the organization, he knew who they were, they went and coached someplace else. He knew who they were and he wasn’t dependent on somebody else’s recommendation or hiring somebody he didn’t know.

"So everybody thinks we have all these people in our organization because it’s creating some kind of advantage for us in the game. No. But we’ve done it here. Mike Groh, he was an intern here. He went to Louisville. He was offensive coordinator at Virginia. I hired him as a [graduate assistant], actually. He went to Louisville, hired him back as a coach.

“That’s happened over and over and over. Billy Napier, same thing. Mike Locksley. All these guys that we had in the organization I knew. ... You have to make a place for them in your organization, so you know and you can bring them up, even if they go someplace else you know you’re going to hire them back.”