Teenager Victoria Mboko produced the shock of the tournament as she defeated top seed Coco Gauff to reach the quarter-finals of the Canadian Open in Montreal.

The 18-year-old Canadian, who was handed a wildcard entry into the main draw, needed just 62 minutes to defeat the two-time Grand Slam champion 6-1, 6-4 and continue her meteoric rise up the rankings.

Mboko converted four of five break points against Gauff and has now dropped just one set in four matches at the tournament.

"Coming into the match, I was so locked in," Mboko said.

"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."

She began the year ranked 333rd in the world, and proceeded to win 22 successive matches without dropping a set on her way to securing five titles on the second-tier ITF Tour.

Mboko entered the tournament ranked 85th, but victory against Gauff will move her up to 53rd, and in the quarter-finals, she will face Jessica Bouzas Maneiro, ranked just two places higher.

Gauff once again struggled with her serve, committing six double faults to take her tournament total to 43 in three matches.

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

Meanwhile, second seed Iga Swiatek cruised into the last 16 with a 6-2, 6-2 victory against Eva Lys.

In Toronto, Casper Ruud suffered a 6-4, 7-5 defeat against Karen Khachanov, before top seed Alexander Zverev advanced to the quarter-finals with a walkover victory against Francisco Cerundolo.

Fifth seed Holger Rune threw away an early lead to lose 6-4, 2-6, 3-6 to Australian Alexei Popyrin.