Muhammad Ali was admitted to an undisclosed hospital Saturday morning with what his representatives are calling a "mild" case of pneumonia, according to the Louisville Courier-Journal.
According to a news release from the family, the prognosis for the 72-year-old boxer, who has battled Parkinson's disease for decades, is considered good. And because the Louisville native was treated early, his stay is expected to be short, the release said. The family declined to disclose more information, citing privacy.
At the premiere of the "I Am Ali" documentary in October, Rahman Ali reportedly said his brother's health had declined to the point that he was too ill to speak, the Courier-Journal reported.
But after that, Ali took to Twitter, posting "Don't believe the hype. Feeling great . . . " on Oct. 14. He also appeared at the University of Louisville's Oct. 30 football game against Florida State.
"Muhammad is doing fine at this point," family spokesman Bob Gunnell told the Courier-Journal in October. "His speaking style is lower in tone, and as the day goes on, he doesn't speak as well as he does in the morning. But Muhammad's a strong person for his age and for the disease he has."
The flamboyant and controversial Ali, born Cassius Clay, won the heavyweight title three times, in 1964, 1974 and 1978. He fought some of the greatest bouts in the sport's history against Joe Frazier and George Foreman.
His motto, "Float like a butterfly, sting like a bee," described his fluid and gracefully style. He became one of the most successful, quotable and famous athletes around the world. He also was a champion of civil rights, openly espousing his thoughts at a time when athletes were generally mum on the topic.
In 1967, three years after winning the first of his titles in a stunning upset of Sonny Liston, Ali converted to Islam and -- citing his religious beliefs -- declared that he would not be conscripted into the U.S. Army. He was arrested and convicted of draft evasion and stripped of his title. He would not fight again for four years, and the case made it to the Supreme Court, where it was overturned.
He became an icon for the counter-culture, opposing the Vietnam War and backing the civil rights movement.
Although his Parkinson's disease, first diagnosed in 1984, has severely limited his ability to travel and to speak, he has been honored worldwide. He lit the flame for the 1996 Olympics in Atlanta and was considered the titular bearer of the Olympic flag in the opening ceremony of the 2012 London Olympics. Ali, then as Cassius Clay, won the gold medal for the U.S. in the 1960 Olympics in Rome as a light heavyweight.
In 1999, Sports Illustrated named him Sportsman of the Century and the BBC named him Sports Personality of the Century. In 2005, President George Bush awarded him the Presidential Medal of Freedom.
Staff and wire reports