Will Smith on Playing Muhammed Ali

Dec. 13 -- For eight years, Will Smith refused to take on the role of Muhammad Ali, saying he didn't believe he was up to the job of playing the man he calls "the greatest figure over the last 100 years."

"Intellectually, I didn't feel that I possessed what it took to become Muhammad Ali," Smith told Primetime's special correspondent Tavis Smiley. "I absolutely, positively did not want to be the dude that messed up the Muhammad Ali story."

Ali and his family even personally asked Smith to take the part. But it was the film's director, Michael Mann, who finally convinced Smith that he'd be able to capture every aspect of Ali in the bio-pic.

"He said, 'We're going to find the greatest trainers in the world to teach you how to fight,'" Smith recalled. "'We're going to understand every second of Muhammad Ali's life. We're going to understand what he ate … how he viewed the world … how his mother felt about him, how his father felt about him."

With Mann's plan laid out, Smith said he "could really see the road … It was a rough, jagged, uphill road in the rain, but he brought it to light so that I could at least see what the road was."

It was at that point, Smith said, that a "weird confidence" came over him. "I felt confident that this was the role that I was born to play."

Getting It Right

For almost two years, Smith trained his body, rehearsed his voice, and tried to encapsulate the soul of Ali, who changed his name from Cassius Clay when he converted to Islam.

"I picked up the spiritual aspects fairly easily," said Smith. "I understand the basic tenets of Islam, and I had an Islamic instructor."

The most difficult parts, he said, were the physical training and learning Ali's dialect.

Throughout the making of the film, Smith felt Ali's imposing presence and the pressure to get it right. He asked Ali to give him three months before watching him rehearse.

He didn't let Ali down. "He is a perfect actor," the 59-year-old said. "I even thought he was me."