Will Smith wanted approval for real-life adaptation in movie 'Concussion'

LOS ANGELES (KABC) -- Will Smith is currently starring in the fact-drama, "Concussion," in which he plays a doctor who made a medical discovery that changed the world of professional football.

"Concussion" is based on the true story of Dr. Bennett Omalu, a forensic neuropathologist who discovered a football-related brain trauma called CTE. The news did not sit well with the National Football League, which fought his findings.

For Smith - who has played real-life figures before including Muhammad Ali - it was important that Omalu approve of his performance and the movie.

"It's a story about a real person who is going to watch the movie," Smith said. "There is nothing more excruciating as an artist to create something about someone else's life and have to sit there to see what they think."

After a life in music, television and movies, the 47-year-old is finally getting used to the fact that he is an established actor.

"For the first time, walking in, I feel like an elder statesman. But I actually feel really silly like I still want to joke and I still want to play around. It's a transition," he said.

"Concussion" is in theaters nationwide and rated PG-13.