Jessica Gregg of Edmonton and Patrick Duffy of Oakville, Ont., each won gold in the 500 metres at the short-track speedskating nationals on Saturday in Montreal.

Gregg won in a time of 44.209 seconds in the women's final, followed by Montreal's Andrea Do-Duc (44.235) and Valerie Lambert of Sherbrooke, Que., with a time of 56.490 to earn bronze.

Lambert was in second until the last lap when she surged momentarily ahead of Gregg. Caroline Truchon, who was in third place, was penalized for interfering with Lambert in the last turn and causing her to fall.

Truchon was demoted to fourth place after receiving a penalty.

The men's final mirrored the women's in change of leads, a fall and penalty. Francois-Louis Tremblay of Alma, Que., won the race, but was penalized for interference after causing Quebec City's Alexandre St. Jean to fall.

St. Jean led from the start, but fell with fewer than two laps to go.

Duffy, who edged ahead of Francois Hamelin of Sainte-Julie, Que., at the finish line won in a time of 42.360 seconds and Hamelin crossed in 42.538 seconds. Maxime Gauthier of Saint-Lambert, Que., won the bronze in 42.653 seconds.

All 24 male and female skaters receive points toward their overall ranking, starting with first place at 1,000 points, second with 816, third 666, fourth 543 points thru to seven points for 24th place.

The selections wrap up Sunday with 1,000 and Super 3,000 metres.

The tournament, along with the Canadian Open Championships in January, is used to determine the 2013-14 national and development teams and skaters for the Olympic selections in August.