The former champions Andy Murray and Novak Djokovic have punched their fourth-round tickets at the US Open with relatively comfortable victories.
World No.1 Djokovic blew past Sam Querrey 6-3 6-2 6-2 to book his spot, while Murray did things a little bit tougher.
Serbia's Djokovic, who is bidding to reach a fifth straight Flushing Meadows final, needed only 85 minutes to dispatch Querrey, setting up a quarter-final against the German, Phillipp Kohlschreiber.
Britain's Murray, seeded eighth, looked in cruise control early before gritting his teeth for a 6-1 7-5 4-6 6-2 victory over Russia's Andrey Kuznetsov.
He will face ninth-seeded Frenchman Jo-Wilfried Tsonga for a place in the quarter-finals.
Also in action on Sunday was the 16th seeded Spaniard Tommy Robredo, who toppled Australia's Nick Kyrgios in four sets, 3-6 6-3 7-6(4) 6-3.
Robredo will meet the Swiss third seed Stan Wawrinka in the round of 16.
Meanwhile, the New Zealander, Artem Sitak, and his doubles partner Benjamin Becker, were eliminated in the second round by Americans Bradley Klahn and Tim Smyczek 6-4 5-7 3-6.