NEW YORK - 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 yesterday to book his spot, while Murray did things a little bit tougher.
"Sam is big server, very powerful. But he doesn't move that well so I wanted to keep him moving around the court, mix up the pace and get as many returns as possible back," said Djokovic after an 85-minute win which was never in doubt from the time he raced into a 5-0 lead in the first set.
Serbia's Djokovic, the 2011 champion who is bidding to reach a fifth straight Flushing Meadows final, needed only 85 minutes to dispatch Querrey, leaving John Isner as the only American man remaining.
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.
"I got off to a good start and then had a cushion when he got back into the match in the third set," said 27-year-old Murray.
He will face either ninth-seeded Frenchman Jo-Wilfried Tsonga or Spain's Pablo Carreno Busta for a place in the quarter-finals.
Meanwhile Wimbledon champion Petra Kvitova became the fifth top 10 seed to exit the US Open in the first week when she was knocked out by Serbian world No.145 Aleksandra Krunic yesterday.
Five-time women's champion Serena Williams was a comfortable winner, racking up her 75th victory at the US Open.
Third-seeded Kvitova lost her third round tie 6-4 6-4 to pint-sized 21-year-old Krunic, who came through qualifying and had never won a match at a major before this year's event.
Kvitova joins second seed Simona Halep, fourth-seeded Agnieszka Radwanska, Angelique Kerber, the sixth seed, and eighth-seeded Ana Ivanovic in failing to make the fourth round.
Kvitova dropped serve five times and committed 34 unforced errors against the 5ft 4in (1.63m) Krunic who divides her time between the pro tour and studying for a university economics degree.