Canadian teenager Victoria Mboko took down top-seeded American Coco Gauff 6-1, 6-4 on Saturday, thrilling the home crowd as she reached the quarter-finals of the WTA 1000 tournament in Montreal.
The 18-year-old wild card saved all four break points she faced, and broke reigning French Open champion Gauff three times on the way to a comprehensive victory in just 62 minutes.
Gauff, who had a combined 37 double faults as she struggled through her first two matches, was caught flat-footed as the Canadian teen raced through the first set in 25 minutes.
Gauff buckled down in the second, but she was unable to convert three break chances in the seventh game - coming up short on a drop shot and smacking a forehand into the net on the first two.
She gained another chance only to hit a service return long, then flew a volley wide to give Mboko a game point, duly converted when Gauff fired a forehand long.
Down 15-30 in the ninth game, Mboko leveled at 30-30 with a blistering backhand, then closed out the hold for a 5-4 lead.
Serving to stay in the match, Gauff fell in a quick 0-30 hole and double-faulted to give Mboko a match point, on which the American hit a backhand into the net.
Mboko will next play either China's Zhu Lin or Spain's Jessica Bouzas Maneiro.
