 While serving the Canucks O'Flaherty registered three consecutive 20-goal seasons and appeared in a total of 438 regular season games in 1971–1979.When he scored 25 goals in 1974-75, it was the most in a season by an American-born player, breaking the previous mark of 23, set by Tom Williams, in 1962-63.O'Flaherty's record was broken in 1978-79 when Tom Rowe scored 31 goals for the Washington Capitals.