By Bruce Lee’s own admission, Muhammad Ali is one fighter that he thought he could never beat in a fight. Lee had great pride and confidence in the kung fu skills he had acquired over years and years of diligent training, but he apparently recognized that his fighting ability wasn’t necessarily infallible. Lee has said himself that he wouldn’t be able to win if he had to go up against the “Greatest of All Time."

As an expert in Wing Chun and the founder of his own martial arts style (Jeet Kune Do), Bruce Lee was a well-respected kung fu master in Hollywood long before he ever made it big in the movies. Lee, who lived in the area, ran martial arts schools and accumulated a number of pupils eager to learn from him. Even Hollywood stars like Steve McQueen and James Coburn befriended Lee and trained under him as Jeet Kune Do students. And when Bruce Lee attained stardom in Hong Kong, even more became interested in his martial arts prowess. It reached a point where Bruce Lee faced regular challenges from would-be opponents.

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Lee has been involved in quite a few well-documented fights over the years, but hasn’t experienced any confirmed losses. However, the actor has claimed that he would have lost to Muhammad Ali. According to Enter the Dragon director Robert Clouse, Lee commented on a hypothetical match during the making of the movie, which was when Ali was at the height of his fame [via Complex]. In response to constant debates over who’d win, Lee said, “Look at my hand. That’s a little Chinese hand. He’d kill me.” In other words, the boxing champion’s impressive size and strength gave him an advantage that even a person of Lee’s skills wouldn’t be able to overcome.

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While Lee was most likely capable of beating challengers larger and stronger than him, Ali was in a completely different class. Muhammad Ali had a well-earned reputation in the ring and was known for being extremely powerful and surprisingly fast. Though Lee was strong and remarkably quick in his own right, it would be quite difficult (if not impossible) for the 148-pound, five-foot-eight martial artist to take many blows from the heavyweight boxing champion of the world, who packed a great deal of power into every punch. After all, Ali was arguably the best in the history of the sport.

Regardless of what would happen, Lee’s comments reflect the tremendous amount of respect the kung fu icon had for Ali as a fellow fighter. The two never met, but Lee seemingly recognized just how good he was from observing his fights on TV. Deeply interested in Ali’s approach, Lee studied Ali’s fights closely, intent on “getting to know how he thinks and moves”. Bruce Lee even incorporated Muhammad Ali’s footwork into his fighting style and taught his students to do the same.

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