New York, Sep 7 (DPA) Andy Murray ended the storybook return to tennis of American injury victim Taylor Dent with a 6-3, 6-2, 6-2 defeat to join Rafael Nadal in the fourth round of the US Open.

The second-seeded Scot and number three Nadal are keeping pace with top seed Roger Federer, who is bidding for his sixth-straight title at Flushing Meadows and went earlier through into the final 16.

Murray Sunday notched his third win against Dent, who spent more than a year in a body cast after a series of back operations. The 28-year-old ranked 195 returned to the ATP last week in New Haven.

Murray won his 15th match in New York, where he lost the final a year ago to Federer.

The Scot, holder of five titles in 2009, was the first man to win 50 matches this season, and stands 56-8 since January.

Nadal shrugged off the pain of an abdominal strain to complete a 7-5, 6-4, 6-4 win over Spanish compatriot Nicolas Almagro.

But the third seed, who missed Wimbledon with a knee injury, was in no mood to speak of his chances of fronting up for his fourth-round clash.

Nadal called for the trainer after the third game of the third set and was stretched out on the court for a spray and bandage on his abdomen.

'I don't want to talk about injuries, sorry,' the six-time Grand Slam winner said.

'I'm a little bit tired to talk about injuries,' he said. 'I'm here to try my best every day. I won the match in three sets. I'm happy for that. I'm going to try my best next round - that's all.

Argentine threat Juan Del Potro, seeded sixth, advanced over Austrian Daniel Koellerer 6-1, 3-6, 6-3, 6-4.

French seeds moves through with number seven Jo-Wilfried Tsonga defeating compatriot Julien Benneteau 7-6 (7-4), 6-2, 6-4 and Gael Monfils, 13th, advancing 6-3, 6-4, 1-0 when Jose Acasuso retired.