 Following his university career, Falconer went on to play professional football in the Canadian Football League in 1976 with the Ottawa Rough Riders (8 games), the Toronto Argonauts (2 games) and the Hamilton Tiger-Cats (3 games).He was a member of the 64th Grey Cup champion Ottawa Rough Riders.In 1976 during the Rough Rider's run to the Grey Cup Championship against the Toronto Argonauts Doug intercepted a Chuck Ealey pass in the end zone late in the game to prevent a winning drive.