Australian Matthew Ebden struck 20 aces as he defeated well-performed American James Blake to reach the quarter-finals of the ATP Tour’s Atlanta Open.

World No.82 Ebden, who won 88 per cent of his first serve points, claimed the decisive break in the ninth game of the third set in a 6-7 (8-6) 6-4 6-4 second round victory.

He will play his first quarter-final since last October at the Shanghai Masters when he faces Luxembourg’s Gilles Muller in the last eight.

Muller advanced after second seed and two-time reigning champion Mardy Fish was forced to retire from their match midway through the second set.

Fish led Muller 6-4 2-2 before injuring himself while trying to chase down a drop shot.