Number five seed Eugenie Bouchard has been dumped out of the Rogers Cup after losing in three sets to qualifier Shelby Rogers.
Bouchard, who lost to Petra Kvitova in the Wimbledon final last month, had been hoping for an extended run in the city where she was born, but she was eliminated from the tournament in stunning fashion.
Rogers, the world number 113, had come through qualifying to make the main draw in Montreal, and she continued that momentum by registering a bagel set against a perplexed Bouchard.
The Canadian responded to break serve on four occasions to take the second set, but she couldn't build on her improvement as Rogers returned to form in the decider.
The American dominated her opponent's second serve to rattle off six successive games to progress through to the next round with a 6-0 2-6 6-0 triumph.