"Rumble, young man, rumble," used to be his battle cry.
But Muhammad Ali is an old man now, ravaged by his years in the ring and his decades of braving Parkinson's disease. The voice that used to bellow that he was "The Greatest" is muted now, save for those times in the mornings when he is able to whisper his thoughts.
The face, though, is still that of the most recognizable man on earth. Maybe not as finely chiseled as it was in his prime, but close enough.
"It's not like he doesn't look like himself," said his oldest daughter, Maryum "May May" Ali. "It's the same face, the Parkinson's hasn't affected that."
Ali turns 70 on Tuesday, giving Baby Boomers who grew up with him one more reason to reflect on their own advancing years.
He's fought Parkinson's the way he fought the late Joe Frazier, never giving an inch. But it's a fight he can't win, and nearly 30 years of living with it has taken a heavy toll.
"He would always just say to his family, 'These are the cards I was dealt, so don't be sad'," Maryum Ali said.
How Ali got the incurable disease will never be known. What is known is that patients gradually lose brain cells that produce dopamine, a chemical key to the circuitry that controls muscle movement. Ali once calculated that he took 29,000 punches to the head in a career that spanned more than two decades.
By the final stages of his career, he was slurring his words. Not long afterward, he was diagnosed with Parkinson's.
Ali's fights often went 15 rounds and he would often stick his head out and dare opponents to land punches. The stories of his legendary battles with Frazier and Foreman are etched in the fabric of the times, monuments to a sport that has never been the same since he retired.
Back then, no one could have imagined the Ali they see now. Bombastic on the stage, he taunted opponents and teased world figures, once telling Philippines president Ferdinand Marcos: "I saw your wife. You're not as dumb as you look."
"He could do things a lot of people wanted to do but couldn't do," said senior sports correspondent Ed Schuyler Jr., who covered Ali's fights. "He was Muhammad Ali. There will never be another like him."