Will Smith, who portrayed Muhammad Ali on the big screen, says the late boxer changed his life.
Ali, 74, died at the weekend after a three-decade long battle with Parkinson's disease.
His death saw an outpouring of grief around the world, mixed with relief he was now finally free of the debilitating condition.
"You shook up the World! My Mentor & My Friend. You changed my Life. Rest in Peace," 47-year-old Smith wrote on Facebook, sharing two photos of himself and Ali.
The 2001 movie Ali, directed by Michael Mann, also starred Jamie Foxx, Jon Voight and Jada Pinkett Smith. It covered Ali's glory years of 1964 through to 1974's Rumble in the Jungle fight against George Foreman.
Last year Smith honoured Ali at the Sports Illustrated Sportsperson of the Year ceremony, as the Legacy Award was renamed the Sports Illustrated Muhammad Ali Legacy Award.
"For nearly two years, I worked to transform myself into the man who changed his name from Cassius Clay to Muhammad Ali and shook up the world, and that's really what makes my job so beautiful," Smith said.
"As an actor, for four or five months at a time, I get to wear people's lives, so I got to wear Muhammad Ali's greatness."
Smith was just beginning to get over the death of his friend Prince, who died in April.
"I am stunned and heartbroken," he wrote at the time. "I just spoke with him last night."
Newshub.
