The film contains moments showcasing Muhammad Ali's celebrated humor and sharp responses, though it’s generally a lengthy and weighty portrayal of Cassius Clay’s life, from his humble beginnings to his dominance both inside the boxing ring and in manipulating the television media that was then profiting from this increasingly worldwide sport. Will Smith becomes the focus following his gold medal win at the Tokyo Olympics in 1964, and similar to many boxers throughout history, his character provides hope for those struggling—a chance to rise above their circumstances through dedication and effort. He embodies the idea that hard work can lead to fame and wealth, suggesting others could achieve the same. Michael Mann then presents a biographical account of this man, exploring his shortcomings, spiritual convictions, government prosecution when he declined induction into the Vietnam War, and associations with prominent figures in the civil rights movement, including Malcolm X, portrayed by Mario Van Peebles. The film depicts a believable, imperfect person—a confident and astute individual who understands how to generate publicity to sustain his public image. Smith is well-supported here by Jamie Foxx as "Bundini," the patient Angelo Dundee (Ron Silver), and Jon Voight as his balding counterpart from ABC television, Howard Cosell. However, Smith's performance doesn’t quite live up to expectations; he handles the key scenes adequately, likely through rehearsal, but his overall portrayal feels lacking in depth and somewhat artificial. There’s an excess of melodrama and conjecture, and a deficiency of what truly propelled him to household name status—his boxing matches. Considering the potential of this story, the film feels unfocused and surprisingly thin. Perhaps a director's cut, roughly 45 minutes shorter, would have helped.

Source on TMDB