He played 99 games in the National Hockey League for the Pittsburgh Penguins and 37 games in the World Hockey Association for the New England Whalers in 1973–76. He was also a member of the United States national team at the 1973 World Championship.
McManama played for the Harvard Crimson from 1969 to 1973. Undrafted by the NHL, he had to choose between the Pittsburgh Penguins and the New England Whalers. He chose the Penguins and signed as a free agent.
He became the first Harvard player to make the NHL in almost half a century.
In 1973-74 he only managed 5 goals and 15 assists in 47 games for Pittsburgh while playing some for the Hershey Bears. The following season he did even worse, scoring only 5 goals and 9 assists on 40 games.
Frustrated and tired, he retired from hockey in 1976 at the age of 24.