Mardy Fish had to come from a set down to beat Juan Monaco and reach the quarter-finals of the Rogers Cup in Toronto.
The American squandered three break points in the opening set as seventh seed Monaco won it 6-2.
However, 11th seed Fish blasted through the second 6-1 before sealing the victory with a 6-4 triumph in the third after saving six break points.
His opponent in the last eight is Richard Gasquet following the Frenchman's win over Tomas Berdych.