RIO DE JANEIRO -- Aurelie Rivard touched the wall, looked up at the time clock and smacked the water with delight.

The Canadian swim star demolished the field to win the 400-metre freestyle at the Rio Paralympics on Thursday, shattering the world record in the process.

"Oh man, I'm so happy, I really wanted it. I was so so so nervous before the race," Rivard said, before darting away to prepare for the 4x100 freestyle relay. "I've been training for it for so long and now that I've done it, it's just so amazing."

It was her third gold -- and fourth medal -- of the Games.

The 20-year-old from Saint-Jean-sur-Richelieu, Que., who was born without a hand, pulled away over the final 200 metres to touch in a world-record four minutes 29.26 seconds. The previous mark was 4:32.79.

Australia's Monique Murphy was second in 4:35.09.

Benoit Huot of Longueuil, Que., captured the 20th medal of his illustrious career, winning bronze in the 400 free in likely his final Paralympic appearance.

"It's number 20, I can sleep in peace now. I can go in peace. I just feel it's a nicer number than 19," said a grinning Huot.

The 32-year-old, who was born with a club foot, flipped backwards over the lane rope in celebration when the results flashed up.

Ukraine swept gold and silver, with Maksym Krypak breaking the world record to win in 3:57.51. Denys Dubrov was second in 4:00.11.

Huot finished in 4:04.63, a couple of seconds faster than he'd predicted he'd swim.

"But the magic came out, I had an amazing first 200, I knew I had to be aggressive and stay with the guys and not be behind like I often do," he said.

Huot said he might swim one more season, but doesn't have another four years of Paralympic preparation in him.

"I'd like to maybe leave on a good note," Huot said. "I would've written a Hollywood script and hoping to finish like this, and I don't think it would have been possible to happen. And it did."

Huot, who is competing in his fifth Paralympics, said he made sure to cherish every moment Thursday.

"Behind the blocks, shaving down this afternoon, telling myself 'Ben, it's the last time.' Putting that suit on, 'Ben, it's the last time.' Going to warmup, 'Ben it's the last time,' " he said. "And I look up at the stands right before the race, and I just said to myself: 'Ben, have the time of your life.' And my mind was in that zone for those four minutes."

In track and field, wheelchair racer Brent Lakatos of Dorval, Que., captured bronze in the 800 metres for his third medal of the Games. The 36-year-old won gold in the 100 and silver in the 400.

Lakatos raced to a time of 1:41.09. Thailand's Pongsakorn Paeyo won gold in 1:40.78, while Pierre Fairbank of France was second (1:40.97).

In cycling, Charles Moreau of Victoriaville, Que., was third in the road race for his second bronze medal of the Games.

Canada's wheelchair rugby team improved to 2-0, beating Britain 50-49 in overtime.