The director of Tiger Woods' documentary is shocked by how loyal his former mistress and caddie still are to the golfing legend

• "Tiger" director Matthew Hamachek told Insider that the biggest surprise in making the movie about the golfing legend was how loyal people are to Tiger Woods — even the ones he has scorned.
• That includes his former mistress, Rachel Uchitel, and his fired caddie Steve Williams, who both took months to decide to participate in the documentary.
• "Even the people who were scorned by Tiger [or] had a bone to pick with him, they are fiercely protective of him," he told Insider.
• "Tiger" is now available on HBO Max.

Over the two-plus years working on the Tiger Woods two-part documentary, "Tiger," directors Matthew Hamachek and Matthew Heineman spent most of their time trying to gain the trust of Woods' inner circle.

Though they succeeded in landing fantastic interviews with those who knew the golfing legend best - for others, including his ex-mistress Rachel Uchitel, his former caddie Steve Williams, and his first love, Dina Parr - it wasn't that easy.

Still, when the duo did eventually land the essential interviews, which show a more intimate side of the golfer, Hamachek said he was shocked by what they told him or moreso what they didn't tell him.

Read more: HBO's explosive Tiger Woods documentary features interviews from people who know the golfing legend best including his former mistress- Here's how the directors got them to talk

"Even the people who were scorned by Tiger [or] had a bone to pick with him, they are fiercely protective of him," he told Insider.

Hamachek said he met with Uchitel before production started and eventually she was the first interview they filmed for the movie. Still, it took months for her to finally agree despite the fact that her affair with Woods, while he was married to Elin Nordegren, caused her life to be "a living hell" for the last 10 years.

Getting Williams also took months to land though he and Woods had a falling out. As we see in part two of the documentary, Williams is fired after Woods gets injured and Williams decides to work for another PGA Tour player, Adam Scott. However, in the movie he still says he "admires" Woods.

Perhaps the hardest interview to land was Parr. In part one of the documentary, Woods sends her a handwritten breakup letter to her out-of-the blue.

Hamachek said it was so difficult to convince Parr to appear in the documentary that he and a producer had to wait outside her home one day to finally talk with her about why she should be involved.

Read more: The director of HBO's Tiger Woods doc revealed that the golfer's former mistress Rachel Uchitel appeared in the movie because she felt the media had 'turned her into a caricature'

The director told Insider that he's happy all three participated in his project as they all reveal fascinating insights on Woods.

And although he doesn't believe any of them contacted Woods to get his approval to be in the movie, Hamachek did find it interesting how much they still care for the golfing legend.

"That was the most surprising thing," Hamachek said, "the loyalty and caring they still have to this day for him despite breakups or being fired."

"Tiger" is available now on HBO Max.