[2] Clancy became famous as a trainer for world champion Emile Griffith, and later worked with other famous boxing world champions and top contenders such as George Foreman, Jerry Quarry, Ken Buchanan,[3] and Gerry Cooney,[4] including Cooney in his fight with Foreman.
[5] Clancy was Emile Griffith's only trainer and guided him to world championships in the welterweight and middleweight classes.
[3] In 1983, he won the Sam Taub Award for excellence in boxing broadcasting journalism.
[6] As a broadcaster, he worked for CBS and HBO and was ringside for numerous world championship fights, including the brutal fights between Roberto Durán and Davey Moore, and Marvelous Marvin Hagler and John "The Beast" Mugabi.
Also for Hagler vs. Sugar Ray Leonard as well as the "One For The Ages" fight between Michael Moorer and George Foreman.