Coco Gauff survived 15 double-faults on Thursday to squeeze out a 7-5, 4-6, 7-6 (7/4) win over Aryna Sabalenka to reach the WTA Toronto Masters quarter-finals.
The American adolescent was responsible for roughly half of the game's errors, while her opponent was responsible for 18 extra doubles.
The third-round marathon match between number six Sabalenka and tenth seed Gauff lasted three and a half hours. Gauff advanced to her maiden Grand Slam final at the French Open this year.
Gauff completed with nine aces and held off 10 of her 14 break points.
The 18-year-victory old's came the next day after she defeated Wimbledon champion Elena Rybakina in a match that lasted two and a half hours.
Simona Halep, a two-time Grand Slam champion, will oppose Gauff on Friday after the former world number one from Romania overcame Switzerland's Jil Teichmann 6-2, 7-5 in 91 minutes.