Dundee died Wednesday at a Clearwater, Fla., rehabilitation center, said his son, James. He had a blood clot that developed during a flight back to his Florida home after visiting Ali in Louisville, Ky., for the boxer's 70th birthday last month.
Other boxers trained by Dundee included George Foreman, Carmen Basilio and Willie Pastrano.
In a sport of drama and explosiveness, dealing with fighters spouting hyperbole and filled with emotion, Dundee was the perfect complement, always calm, always analytical, ever able to maintain his cool, whether in the sweltering heat of Manila or the fury of Zaire.
In his 2007 autobiography, "My View From the Corner," Dundee said his job was "a mixed bag combining certain qualities belonging to a doctor, an engineer, a psychologist and, sometimes, even an actor....When the bell rings ending the round, that's when the trainer takes over."
If Dundee hadn't taken over on two occasions with Ali, one of the greatest careers in boxing history might have ended almost before it began.
At the end of the fourth round of a 1963 fight against Henry Cooper, Ali, then known as Cassius Clay, was surprised by a left-hand punch that floored him and left him dazed. Fortunately for Clay, it was the end of the round, allowing him to stagger back to his corner.
It was there that Dundee, trying to buy time until his fighter's head cleared, stuck his finger in a slight split in the seams of one of Clay's gloves, causing a slightly bigger split. That allowed Dundee to ask the referee for another pair of gloves. None were available, but the incident added valuable seconds to Clay's rest time, allowing him to recover and go on to win on a fifth-round technical knockout.
His next fight, against heavyweight champion Sonny Liston, might not have occurred if Clay had lost to Cooper.
In the fourth round of Clay's 1964 fight against Liston, another crisis occurred. A substance of undetermined origin got in Clay's eyes, temporarily blinding him. In the corner prior to the fifth round, Clay ordered Dundee to cut off his gloves, ending the fight.
The trainer would do no such thing. He wet Clay's eyes, alleviating some of the sting, and then literally shoved him back out into the ring when the bell rang. Clay, still unable to see, was told by Dundee to just run.
Run he did until, midway through the round, Clay's vision cleared. At the end of the sixth round, Liston, claiming a shoulder injury, quit in his corner.
Thanks to Dundee, Clay had his first title and a launching pad for the meteoric career that would follow.
Dundee was born Angelo Mirena on Aug. 30, 1921, in Philadelphia, the eighth of nine children. It was his brother Joe, 21 years his senior, who first took the name Dundee to hide the fact he was a fighter from his father. His brother Chris also took the name, as did Angelo eventually.
Dundee's introduction to boxing came during his time in the U.S. Army Air Forces during World War II. He worked the corner in service boxing tournaments.
Dundee's course in life was set. He would follow his brother Chris, a future Hall of Fame promoter, to New York where Dundee would hone his trade at Stillman's Gym, and then on to the Fifth Street Gym in Miami where his reputation was sealed.
He became Ali's trainer in 1960 for Ali's second pro fight and remained with him until the end, 21 years later. Even when Ali was surrounded by members of the Black Muslims and mired in racial controversy, Dundee, a white man, was able to remain under the radar and do his job.
Dundee added an Olympic gold medal winner to his stable of fighters when Leonard joined him after turning pro. Leonard won the medal in 1976.
Dundee's most memorable moment in Leonard's corner came in 1981, in Leonard's first fight against Hearns. Momentum had slipped away from Leonard by the end of the 12th round of the 15-round match.
"You're blowing it, son," Dundee told him in the corner.
Leonard responded by rallying for a 14th-round TKO victory.
As he had with Ali, Dundee had again possibly saved a Hall of Fame career, ensuring himself a spot among the pantheon of boxing trainers.
Besides his son, James, Dundee is survived by his daughter, Terri, six grandchildren and one great-grandchild. His wife, Helen, died in 2010.
Springer is a former Los Angeles Times staff writer.
Los Angeles Times staff writer Lance Pugmire contributed to this report.