Roger Federer and Novak Djokovic remain in contention to win the US Open after reaching the quarter-finals in New York.
Five-time champion Federer, 11/2 with bet365 to win the tournament, thrashed Juan Monaco 6-1 6-2 6-0 in just 82 minutes and will now meet Jo-Wilfried Tsonga in the last eight.
He will be out for revenge after losing a five-set epic to the Frenchman at Wimbledon earlier this year.
World number one Djokovic, 5/6 to claim his third Grand Slam of the year, is seeded to face Federer in the semi-finals after edging past Alexandr Dolgopolov.
The Serb was pushed hard in a first set tie-break, eventually winning it 16-14, before cruising to a 7-6 6-4 6-2 success.
Djokovic will now face compatriot Janko Tipsarevic in the quarter-finals after he got the better of Spain‘s Juan Carlos Ferrero.