Russia's Liudmila Samsonova upset Aryna Sabalenka in three sets to book her place in the quarter-finals of the weather-hit WTA Montreal Open on Friday.
Samsonova, seeded 15th, battled into the last eight with a 7-6 (7/2), 4-6, 6-3 win over the second-seeded Sabalenka, the reigning Australian Open champion from Belarus.
The last-16 clash in Montreal had been shunted into the Friday morning schedule after heavy rain wreaked havoc with Thursday's play at the hardcourt tournament, a US Open tuneup.
It means Samsonova will return later Friday to face either Belinda Bencic of Switzerland or Petra Kvitova in the quarter-finals.
Bencic and Kvitova were also handed an early start on Friday after their last-16 match was held over due to Thursday's weather disruption.
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