Founded in at least the 1940s as the Owen Sound Mohawks, the team was a member of the OHA Senior A league.

The Mercurys made it back to the OHA Senior A final again in 1951, and defeated the Sarnia Sailors 4-games-to-2 to win the J. Ross Robertson Cup.

The Canadians drove all the way from Fort Frances, Ontario on the Manitoba border to compete with the Mercurys at the Centennial Arena.

Unlike 1952, the Mercurys took it to the Indians and swept the series 4-games-to-none to win their second J. Ross Robertson Cup in four seasons.

[1] The Mercurys did not make it to the 1954 Allan Cup final, as the Eastern Championship went to the Northern Ontario Hockey Association's Sudbury Wolves.

In 1956-57, the OHA Senior A league absorbed many teams from the Ottawa District Hockey Association.