Canada's Brittany Maclean competes in the women's 400-metre freestyle heat at the Aquatic Centre in the Olympic Village at the 2012 Summer Olympics in London on Sunday, July 29, 2012.Sean Kilpatrick/The Canadian Press
Brittany MacLean of Mississauga, Ont., set a Canadian record to advance to the women's 400-metre freestyle final on Sunday at the Rio Olympics.
She finished her heat in four minutes 3.43 seconds to move on to the event's final later Sunday night.
"That first race is a little bit much, but it's good to get the butterflies out and hoping to go faster tonight," said MacLean.
Vancouver's Emily Overholt finished seventh in her heat and did not advance.
Canada's men's 4x100 freestyle relay team qualified for their final, placing fifth in the rankings after completing their heat in 3:14.06.
Santo Condorelli of Kenora, Ont., Calgary's Yuri Kisil, Markus Thormeyer of Newmarket, Ont., and Evan van Moerkerke of London, Ont., will compete in that final later Sunday.
"I think there's a lot more there. I think each one of us has a couple tenths (of a second) that we can shave off," said van Moerkerke. "I know the excitement tonight's going to be unreal."
Earlier Sunday, Canadian swimmers Kylie Masse, Dominque Bouchard and Rachel Nichol advanced to the semifinals of their respective 100-metre races.
Masse, of LaSalle, Ont., and Bouchard, of North Bay, Ont., both advanced in the backstroke while Nichol, of Lethbridge, Alta., moved on in the breaststroke.
Masse finished with a third best overall time in the heats at 59.07 seconds. Bouchard qualified in 12th place with a swim of 1:00.18.
Nichol had an 11th best time of 1:06.85 in the breaststroke. Kierra Smith of Kelowna, B.C., finished 18th and failed to qualify for the next round.
The top 16 swimmers advance to the semifinals in both disciplines. The semis for both were scheduled for Sunday night.