The only one who seemed unconcerned was Ali

"Before the much anticipated fight (dubbed by Ali as the "Rumble in the Jungle"), in Ali's dressing room, Ferdie Pacheco remembered a mood of palpable dread prevailed. 'The question,' he said, 'was how much damage would Foreman do.' The only one who seemed unconcerned was Ali.... Meanwhile, in Foreman's dressing room, former lightweight champion Archie Moore also felt dread. 'I was praying,' said Moore, 'and in great sincerity, that George wouldn't kill Ali. I really felt that was a possibility.'" 
     — from Men's Journal magazine

I love that so much. I effing love it! Gives me goosebumps every time I read it, remember it, say it: The only one who seemed unconcerned was Ali.

Ali, of course, won the fight, surprising everyone except himself. And everyone was surprised years earlier when he knocked out Sonny Liston... everyone except Ali himself.

Love it.

And years later, Foreman even added this about the Rumble in the Jungle, "Probably the best punch of the night was never landed. Muhammad Ali, as I was going down, stumbling, trying to hold myself, he saw me stumbling.... Ordinarily you finish a fighter off; I would have. He got ready to throw the right hand, and he didn't do it. That's what made him, in my mind, the greatest fighter I ever fought." 
     — from the movie Facing Ali

"I'm so quick, I flip the switch and I'm in bed before the lights go out."
     — Muhammad Ali