What a day for Penny Oleksiak.

On Saturday afternoon, the 16-year-old swimmer from Toronto set a new Canadian and world junior record in the women’s 100m butterfly, with a time of 56.73 seconds.

Later that night, in the semifinals, she finished third in her heat with the fifth-fastest overall time, to qualify for Sunday’s final.

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Sweden's Sarah Sjostrom, left, and Canada's Penny Oleksiak compete in a semifinal of the women's 100-meter butterfly during the swimming competitions at the 2016 Summer Olympics, Saturday, Aug. 6, 2016, in Rio de Janeiro, Brazil. (AP Photo/David J. Phillip)

Sweden’s Sarah Sjostrom, left, and Canada’s Penny Oleksiak compete in a semifinal of the women’s 100-meter butterfly during the swimming competitions at the 2016 Summer Olympics, Saturday, Aug. 6, 2016, in Rio de Janeiro, Brazil. (AP Photo/David J. Phillip)

The best was saved for last, when she swam the anchor leg of the 4x100m freestyle relay final, helping Canada win its first medal of the Rio Games (a bronze), and the nation’s first medal in the event since Montreal 1976.

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But if the first-time Olympian was feeling psychological pressure, she didn’t show it.

“I wasn’t super nervous just because the other three girls had gone out already and I knew they were all going to do their job,” said Oleksiak.

Sandrine Mainville, Chantal Van Landeghem, Taylor Ruck, and Penny Oleksiak celebrate winning bronze in the Women's swimming 4 x 100m Freestyle Relay Final qualifying at the Olympic games in Rio de Janeiro, Brazil, Saturday August 6, 2016. COC Photo/Mark Blinch

Sandrine Mainville, Chantal Van Landeghem, Taylor Ruck, and Penny Oleksiak celebrate winning bronze in the Women’s swimming 4 x 100m Freestyle Relay Final qualifying at the Olympic games in Rio de Janeiro, Brazil, Saturday August 6, 2016. COC Photo/Mark Blinch

“They got us exactly where we needed to be for the last leg and, I mean, I just dove in and did my thing.”

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She also wasn’t feeling the physical pressure, despite having less than an hour between her butterfly semifinal and the freestyle relay final.

“I’m only 16 so I don’t get as much lactic acid; I mean, an hour is so much time for me,” she said. “When I was in age-group meets, I had maybe five minutes between races.”

Penny Oleksiak, of Canada, swims in the Women's 100m Butterfly semifinal at the 2016 Olympic Games in Rio de Janeiro, Brazil on Saturday, Aug. 6, 2016. THE CANADIAN PRESS/Frank Gunn

Penny Oleksiak, of Canada, swims in the Women’s 100m Butterfly semifinal at the 2016 Olympic Games in Rio de Janeiro, Brazil on Saturday, Aug. 6, 2016. THE CANADIAN PRESS/Frank Gunn

The plan to bring Oleksiak in for the relay final (she hadn’t taken part in the heats earlier on Saturday) clearly paid off. Now, with one medal already in the books, it’s suddenly seeming like anything could be possible for the youngster and her fellow Canadian swimmers.

“No one really expected this from Canada coming into the meet,” said Oleksiak. “But now that we’re here, people are going to be surprised at what we do.”