(Photo credit: Eric Bolte-Imagn Images)

Canadian teenager Victoria Mboko delivered the biggest victory of her career on Saturday when she dominated top-seeded Coco Gauff 6-1, 6-4 to advance to the quarterfinals of the National Bank Open in Montreal.

Mboko needed just 62 minutes to dispose of the two-time Grand Slam champion.

'It's incredible,' Mboko said in French in her on-court interview, according to the WTA. 'I'm so happy to beat such a great champion.'

Mboko, 18, received a wild card entry into the tournament and has dropped just one set in four matches. She is the youngest Canadian quarterfinalist at this event since 17-year-old Helen Kelesi in 1987.

Mboko began the year ranked No. 333. She was at No. 85 entering this event and rose to No. 53 with the win over Gauff.

Mboko, a Toronto resident, saved all five of her break-point opportunities and converted 4 of 5 against Gauff. She won 15 of 27 points (55.6 percent) against Gauff's second serve.

'Coming into the match, I was so locked in,' Mboko said in a postmatch interview with Sportsnet. 'I tried to keep my composure as much as I could, especially playing in front of so many people. This is a very special experience for me.'

In May, Gauff lost the first set in a second-round match in Rome against Mboko before rallying to win the next two.

The second meeting belonged to Mboko.

'I'm sure we're going to have many more battles in the future,' Gauff said after the loss. 'Yeah, I think she's going to have a lot of success on tour.'

Gauff again had troubles with her serve as she committed six double faults for a three-match tournament total of 43.

In the second round, she had 23 while narrowly beating Danielle Collins in a third-set tiebreaker in the second round and then followed up with 14 in a three-set, third-round win over Russia's Veronika Kudermetova.

Mkobo will face either Spain's Jessica Bouzas Maneiro or China's Link Zhu. Those two women were slated to play Saturday night.

No. 9 seed Elena Rybakina of Kazakhstan advanced to the quarterfinals with a 5-7, 6-2, 7-5 victory over No. 30 Dayana Yastremska of Ukraine.

Rybakina overcame nine double faults while recording seven aces and converting 5 of 9 break points.

Yastremska was one game away from winning before Rybakina won the final three games. The clincher came when she converted her fourth-match point attempt of the decisive game.

Yastremska had four aces against seven double faults.

Rybakina will face No. 24 seed Marta Kostyuk on Monday. The Ukrainian rallied for a 5-7, 6-3, 6-3 victory over No. 28 McCartney Kessler.

Both players had substantial serving issues. Kostyuk scored the lone ace of the match but had 10 double faults. Kessler was worse with 12.

Kessler pulled within 4-3 in the third set before Kostyuk won the final two games to sew up the win.

--Field Level Media