While heading to a gym in Oklahoma City to host his annual basketball camp, Kevin Durant sent a text message to Team USA Coach Mike Krzyzewski to let him know that he needed to talk about something important. Durant had made up his mind that he was drained and could no longer dedicate his summer to training and playing for USA Basketball.

His family, friends and representatives all understood and supported Durant but the hard part was going to be backing out and disappointing the people – like Krzyzewski – who expected him to play a leadership role in the pursuit of another international gold medal. A few days before he reached out to Krzyzewski, Durant watched Indiana Pacers forward Paul George break his right leg in a horrific collision with a basket stanchion during a Team USA basketball scrimmage in Las Vegas that convinced the reigning NBA MVP to withdraw from the FIBA World Cup.

“It took everything out of me seeing that,” Durant later told friend Randy Williams and a Nike executive at his camp of George. “Everything I had to play for Team USA, that injury stripped it away from me.”

Shortly thereafter, Durant was eating lunch when someone handed him his telephone. “That’s him?” Durant asked.

What followed is probably the most compelling part of the hour-long HBO Sports documentary, “The Offseason: Kevin Durant,” which will air Tuesday at 10 p.m. on HBO. Durant allowed cameras to track the summer following his first MVP season – from Oklahoma City’s season-ending loss to San Antonio in the Western Conference finals to training camp, where the eighth season of his career was delayed by at least one month because of a broken right foot.

The film, directed by Brendan and Emmett Malloy, started with footage of Durant’s emotional MVP speech and captured Durant as he worked out with Steve Nash and teammate Russell Westbrook in Los Angeles, failed to lure Pau Gasol to the Thunder, traveled home to Washington to unveil his latest Nike shoe, spent a week training with USA Basketball in Las Vegas, played pickup with Carmelo Anthony in New York, and flirted with Under Armour before signing a humongous, 10-year, $275 million contract to remain with Nike.

“It was cool to see how moved people were by my speech, but that’s not what I’m here to do,” Durant said early in the film. “I’m in this league to win a championship.”

Durant fares better in the reality special than in his feature film debut, “Thunderstruck.” During one scene, Durant’s agent, Rich Kleiman of Roc Nation Sports, got upset after a reporter violated terms of an interview agreement and mistakenly asked Durant about becoming a free agent next summer. Durant politely corrected the reporter and told her that he is actually signed for two more years with the Thunder and wasn’t thinking beyond that.

Durant, however, does appear to predict the future for LeBron James while watching the Spurs clobber the Miami Heat in five games in the NBA Finals.

“LeBron is gone if they lose this series, dog,” Durant shouts at his television to no one in particular.

When the subject of Durant possibly returning home to play for the Wizards is raised during a group interview session in Las Vegas, the film conveniently left out his response, which gained traction nationally last July. Durant’s angst about playing for Team USA – especially after George went down – is reflected, setting the stage for his difficult conversation with Krzyzewski.

“It felt awkward,” Durant said of the scrimmage that possibly ended George’s season. “Once we were playing, it just didn’t feel right for some reason.”

After Durant is shown reacting on court to what he called a “freak accident,” the scene shifts to conversation with Durant in which he says, “When you see something like that, so gruesome, in front of you, of course you’re going to think, ‘This could happen to me.’ ”

Durant was noticeably unsettled as he stood on a wall and spoke to Krzyzewski. He later explained, “I feel like I’m letting somebody down and I hate that feeling.”

But Durant was eventually at peace with his decision. The rest helped Durant arrive for training camp refreshed but he couldn’t avoid having his own setback in less than two weeks. The Thunder will have a difficult time holding on in the Western Conference with Westbrook also sidelined, but Durant remained focused and positive about possibly winning his first championship.

“It’s time to get it done,” Durant said at the end of the documentary.