In junior Mancuso was goal scoring right winger with his hometown Cataracts team. They even challenged for the Memorial Cup in 1933.
Mancuso was a fan favorite in Hershey. A newspaper report back then called him "one of the most colorful players ever to perform with Hershey." The article added "he is just a small fellow but he is in there all the time and absorbs plenty of punishment." Another article praised him for "always travelling at a hustling clip, but can't seem to find the net."
In 1937 Mancuso signed with the Montreal Canadiens. While he played most of the year with the New Haven Eagles minor league team, Mancuso did play 17 games for Les Canadiens. Wearing sweater number 15 he scored one goal and one assist.
Mancuso became a mainstay in New Haven over the next five seasons. Montreal only called him for two two-game call ups, one in 1938-39 and one in 1939-40.
Montreal was no league powerhouse back at that time, but they did not seem to find a place for Mancuso in their lineup. In 1942 they traded him to the New York Rangers, who were only a year removed from winning the Stanley Cup. Somehow Mancuso was able to step into 21 games for the Rangers in 1942-43 and contribute six goals and fourteen points.
Mancuso would never find out if he finally could be a NHL regular player. He was called upon by the Canadian military for World War II service, losing two full seasons with no hockey played.
When Mancuso returned he found himself about as far away from the NHL as a player could get in those days - California. Mancuso would play four seasons in the new rendition of the Pacific Coast Hockey League, playing two seasons with the Hollywood Wolves (where he was teammates with Bill Barilko, Cowboy Tom Anderson and Bob Gracie) and two seasons with the Los Angeles Monarchs. Frank Sinatra and Bing Crosby regularly attended games.
Mancuso was released in 1949, bringing an end to his hockey career. But he obviously fell in love with the California sunshine. He stayed there until his death in 2003, passing away in Mission Viejo, Orange County at the age of 89.