Overall Michael Mann's choppy direction and a wandering script really hold back what could have been a great movie. Mann is obsessed with the music of the time period and while at times it does create a nice atmosphere, he also extends several scenes to unneeded length because of it. The script goes into great detail in certain areas of Ali's life, yet leaves other areas strangely glossed over. For instance, a great deal of time is spent on his father, whereas almost none is spent on the relationship between Ali and Joe Frazier, who many consider to be his greatest enemy, most interesting foil, and Ali's greatest triumph, yet the Thrilla in Manilla is not even mentioned.
In the end, it works to a certain extent thanks to a wide range of excellent performances including, Jamie Fox, Jada Pinkett Smith, Ron Silver, Mykelti Williamson, Jeffrey Wright, and especially Jon Voight and Mario Van Peebles. The last two portray historic figures in their own right and give them the proper scope those men deserved, while still being deferential to Ali. Finally, Will Smith gives the finest performance of his career to date and continues to grow as an actor as he impersonates Ali perfectly while creating a flawed, but larger than life man who becomes a legend.
In the end, it works to a certain extent thanks to a wide range of excellent performances including, Jamie Fox, Jada Pinkett Smith, Ron Silver, Mykelti Williamson, Jeffrey Wright, and especially Jon Voight and Mario Van Peebles. The last two portray historic figures in their own right and give them the proper scope those men deserved, while still being deferential to Ali. Finally, Will Smith gives the finest performance of his career to date and continues to grow as an actor as he impersonates Ali perfectly while creating a flawed, but larger than life man who becomes a legend.