Jan. 3, 2007 is a memorable day for Bill Belichick — and not because it came just a few days after his New England Patriots completed a 16-0 regular season.

“One of the best days of my coaching career was the day you took the Alabama job,” Belichick told University of Alabama coach Nick Saban.

“I’m not sure I believe that,” Saban replied.

The respect the UA coach and New England Patriots coach have for one another was on full display in the HBO special, “Belichick & Saban: The Art of Coaching,” a 75-minute show HBO will unveil Tuesday night at 8 p.m. Central. The documentary starts with Saban and Belichick at Alabama’s most recent Pro Day, discussing the players on hand and the nuances of Saban’s inside linebacker play.

Through taped conversations between the two, individual interviews with the coaches and others, the piece tells the story of how both Saban and Belichick got their starts in coaching, how they first met on a coaching staff at Navy and how they both benefitted from Saban’s time as Belichick’s defensive coordinator for the Cleveland Browns.

“I watch what they do and study their scheme because if it’s good enough for Nick, it’s probably good enough for me,” Belichick said.

Saban said his time coaching in the NFL was particularly good for him in learning how to adapt his coaching styles to different kinds of players, which was ultimately useful to him on the college level.

“As soon as the owner pays them, they’re gonna play,” Saban said.

Much of the documentary focuses on the Saban and Belichick approach to coaching in terms of organizational leadership, with insight from others: Georgia coach Kirby Smart; Dallas Cowboys coach Jason Garrett; former NFL leadership Ozzie Newsome, Mike Lombardi and Phil Savage; Saban’s family, wife Terry and children, Nicholas Saban and Kristen Saban Setas; Belichick’s children Stephen, Brian and Amanda; and Belichick’s girlfriend, Linda Holliday.

“Human nature is more survival than it is to be special good,” Saban said. Belichick said he learned that from Saban.

The coaches discuss their distaste of the NFL Combine, how they react to losing, dealing with social media and the technology in the coaching industry developing coaches differently now than it did when they were working their way up.

Smart’s appearance in the piece came as it discussed Saban’s decision to replace Jalen Hurts with Tua Tagovailoa in the 2017 national championship game, but it also comes after Saban and Belichick vent to one another on something former assistants — as Smart is — do.

Saban said he has a tough time with assistants coming to Alabama to improve themselves as coaches then getting bigger opportunities off of that improvement, just to turn around and take Alabama’s people from it. Smart and Tennessee coach Jeremy Pruitt did this to UA.

As Belichick put it, “I’m happy for them, but I want to see them build their own program.”

Reach Brett Hudson at 205-722-0196 or bhudson@tuscaloosanews.com or via Twitter, @Brett_Hudson