In 1960, the young Paduano left Italy to join his father and brother in Québec. As soon as he arrived, Donato joined the Italian Boys Club, where he began boxing. In late 1962, his career as an amateur boxer began when he started to train with Roger Larivée under the auspices of the Palestre Nationale, the venerable French-Canadian amateur athletic association. Under Larivée’s tutelage, Paduano developed his talents as a boxer.
Recognized as a scientific boxer with impeccable technique, Paduano competed in the British Commonwealth Games in Kingston, Jamaica, in 1966. In 1967, he took a bronze medal at the Pan American Games in Winnipeg.
In March 1968, Paduano won the New York Daily News Golden Gloves Championship in the 160-pound Open division. A few months later, he fought as a member of the Canadian boxing team at the Olympic Games in Mexico. In his first bout, he defeated the Nigerian Fidelis Onyesom, but in his second bout, Paduano was defeated in turn by Argentine boxer Mario Omar Guillotti. Shortly after the Olympics, Paduano left the world of amateur boxing, with a record of 83 wins, six losses, and one draw. He fought his first professional match in Shawinigan, Québec on 11 November 1968, starting out on a career that was to earn him the sobriquet of the “Angel of the Ring”.
On 9 December 1969, after a year marked by a string of victories, Paduano defeated Joey Durelle to take the Canadian welterweight title. A few months later, Paduano made an international name for himself by handing Marcel Cerdan Jr. his first defeat in 48 fights, at New York City’s Madison Square Garden. This victory made Paduano the third contender for the world welterweight title. But he then suffered two consecutive defeats, which put him out of the running for a championship match. The first loss occurred on 7 December 1970, when Paduano was beaten in New York by Scottish boxer Ken Buchanan, the reigning world welterweight champion; the second occurred in Montréal, on 18 February 1971, when Paduano lost to fellow Canadian Clyde Gray.
Paduano subsequently pursued his career on the Québec scene, facing talented local boxers such as Jean-Claude Leclair and Fernand Marcotte. His two bouts with Marcotte brought great joy to Québec boxing fans. After the first match, in November 1971, ended in a draw, the two fighters faced each other again three months later. Though Paduano hit the mat once, the Angel of the Ring eventually managed to get the measure of his opponent and win the match by decision.
Paduano continued boxing until 1975. He returned for two bouts in 1976 and fought his last two matches in 1980 before hanging up his gloves for good. In his professional career, he tallied 55 wins, 10 losses, and two draws. He was inducted into the Québec Sports Hall of Fame in 2000.