Samantha Stosur stunned by Lucie Safarova in Rogers Cup

Samantha Stosur has suffered a surprise exit in the third round of the Rogers Cup in Montreal with a straight-sets defeat to Lucie Safarova.

With both players dropping serve in the first set, it was Safarova who pipped the sixth seed in a mammoth tie-break 11-9.

The second also went to a tie-break and it was the Czech 16th seed who won it again, this time 7-5.

Safarova's reward for beating the 2011 US Open winner is a quarter-final encounter with either Roberta Vinci or Angelique Kerber.