In March 2004, Hank Haney received a call from Tiger Woods in which the golf champion asked Haney to be his coach.
It was a call that would change both men's lives. Tiger - only 28 at the time - was by then already an icon, judged by the sporting press as not only one of the best golfers ever, but possibly the best athlete ever.
But Tiger was always looking to improve, and he wanted Hank's help.
Over the next six years of working together, the supremely gifted Woods collected six major championships and rewrote golf history.
Hank was one of the very few people allowed behind the curtain.
Always haunting Tiger was his fear of `the big miss' - the wildly inaccurate golf shot that can ruin an otherwise solid round - and it was because that type of blunder was sometimes part of Tiger's game that Hank carefully redesigned his swing mechanics. Towards the end of their time together, the champion's laser-like focus began to blur and he became less willing to put in punishing hours practicing.
Hints that Tiger hungered to reinvent himself were present in his bizarre infatuation with elite military training, and - in a development Hank didn't see coming - in the scandal that would make headlines in late 2009.
It all added up to a big miss that Hank, try as he might, couldn't save Tiger from. There's never been a book about Tiger Woods that is as intimate and revealing - or one so wise about what it takes to coach a superstar athlete.