While doing press for the film in Russia last Wednesday, the acclaimed filmmaker pushed back against criticism that, in the film, Lee (played by Mike Moh) was too egotistical.
"Bruce Lee was kind of an arrogant guy," Tarantino said. "The way he was talking, I didn't just make a lot of that up. I heard him say things like that, to that effect. If people are saying, 'Well, he never said he could beat up Muhammad Ali,' well, yeah, he did. Not only did he say that, but his wife, Linda Lee, said that in her first biography I ever read. ... She absolutely said it."
Warning: spoilers ahead -- In the film, Lee and stuntman Cliff Booth (Brad Pitt) get in a dispute over just how tough the martial arts legend is after he delivers a long speech in which he claims he could beat the boxer Cassius Clay (aka Muhammad Ali). In order to settle the debate, Lee suggests a best-of-three fight in which both win a round before they're interrupted.
Bruce Lee's daughter, Shannon Lee, previously said she was deeply hurt by the way her father was portrayed in the film.
"I can understand all the reasoning behind what is portrayed in the movie," she told The Wrap in July. "I understand that the two characters [Booth and Rick Dalton, played by Leonardo DiCaprio] are antiheroes and this is sort of like a rage fantasy of what would happen… and they're portraying a period of time that clearly had a lot of racism and exclusion."
"I understand they want to make the Brad Pitt character this super badass who could beat up Bruce Lee," she added. "But they didn’t need to treat him in the way that white Hollywood did when he was alive."
Shannon also touched upon how the fact that her father was the only non-white character in the entire film with a speaking role.
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"Given how sympathetic Tarantino's portrayal of Steve McQueen, Jay Sebring, and Sharon Tate is, I'm surprised he didn't afford the same courtesy to Lee, the only non-white character in the film," she said. "He could have achieved the same effect -- using Bruce to make Brad Pitt's character look tough -- without the mockery."
While in Russia, Tarantino also addressed arguments that he portrayed Lee to appear weaker than he actually was.
"Brad would not be able to beat up Bruce Lee, but Cliff maybe could," the 56-year-old director said. "If you ask me the question, 'Who would win in a fight: Bruce Lee or Dracula?' It's the same question. It's a fictional character. If I say Cliff can beat Bruce Lee up, he's a fictional character, so he could beat Bruce Lee up."
Later, Tarantino elaborated on Booth's backstory, arguing that, because of his experience as a veteran, he'd be able to take on the action movie star -- in certain circumstances.
"The reality of the situation is this: Cliff is a Green Beret. He has killed many men in WWII in hand-to-hand combat," Tarantino said. "What Bruce Lee is talking about in the whole thing is that he admires warriors. He admires combat, and boxing is a closer approximation of combat as a sport. Cliff is not part of the sport that is like combat, he is a warrior. He is a combat person."
"If Cliff were fighting Bruce Lee in a martial arts tournament in Madison Square Garden, Bruce would kill him," he added. "But if Cliff and Bruce were fighting in the jungles of the Philippines in a hand-to-hand combat fight, Cliff would kill him."