Given the limitations, does “Ali” provide fresh insights into the legend that we would not have gotten just by watching an episode of “Biography” on cable’s A&E network? The answer, surprisingly, is yes. We learn that Ali was drawn to the Nation of Islam because he was disgusted as a child at how African-Americans were treated in his hometown of Louisville. When he changed his name from Cassius Clay to Muhammad Ali, his immediate family – particularly his father and brother – was mortified. Other tidbits we learn is that Ali was in deep financial trouble after his refusal to accept induction into the army in 1967. And despite being a Muslim, he enjoyed being a playboy even when married. “I should have waited until I was 50 before becoming a Muslim,” he quips late in the film.

Michael Mann does a particularly good job investigating the political tensions in the Nation of Islam hierarchy at the time Muhammad Ali came into national prominence. The feud between NOI founder Elijah Muhammad and one-time disciple Malcolm X is well-known and was a prominent part of Spike Lee’s 1992 biopic of Malcolm X. Lee, however, did not discuss Ali’s eventual denial of Malcolm X in favor of Elijah Muhammad, a decision that had long-term effects on Ali’s mind. In “Ali,” Mario Van Peebles’ portrayal of Malcolm X is remarkably believable.

“Ali” is not a full-fledged biography because it focuses on his life only from 1964 through 1974, when, against all odds, he regained the world heavyweight title by knocking out George Foreman in the “Rumble In The Jungle” in Zaire. Michael Mann was perhaps too influenced by Martin Scorcese’s 1980 masterpiece “Raging Bull,” as he spends too much of the two-and-a-half hours showing Ali in the ring pummeling the likes of Sonny Liston, Ernie Terrell and George Foreman. Flipping on ESPN Classic could offer the same material.

Furthermore, Mann does not give us any additional insights into the infamous title rematch with Liston on May 8, 1965 in Lewiston, Maine, when Ali knocked him out in one round. It appeared that Liston hit the canvas on a punch that no one saw, and the consensus has long been that Liston took a dive that night.

Will Smith captures Ali’s mannerisms and verbosity perfectly. Throughout, he is helped by a supporting cast that is equally game: Jamie Foxx is terrific as Ali’s sharp-witted cornerman Drew Bundini Brown, as is the virtually unrecognizable Jon Voight, who avoids the usual cliches in his portrayal of ABC legendary sportscaster Howard Cosell. On the debit side of the ledger, Mann gives few lines to the usually superb Ron Silver and Paul Rodriguez, who play trainer Angelo Dundee and Dr. Ferdie Pacheco, both key members of Ali’s entourage.

To use boxing parlance, “Ali” is far from a knockout, but I will give it the decision.