No worry for Murray

The British world number two was never in any serious trouble against the big-serving serve and volleyer, taking the contest 6-3 6-2 6-2 in just one hour and 30 minutes at Arthur Ashe Stadium.

Murray, who reached the final last year before losing to Roger Federer, will now play Croatian 16th seed Marin Cilic for a place in the quarter-finals on Tuesday.

Dent, 28, had defied the odds to reach the third round in his first appearance at the US Open since 2005.

In the intervening period, he underwent two operations on his back having suffered a break in his bottom vertebrae and fell from 21st in the world to completely out of the rankings.

Now back to 195th, the Californian lost in the first round at both this year's Australian Open and Wimbledon but he justified his wild card in New York with victories over world number 37 Feliciano Lopez and then claimed another Spanish scalp in Ivan Navarro in a five-set, serve-volley epic on Friday night.

There had been 255 net approaches between he and Navarro but Murray was a very different prospect for the big-serving Dent. The Scotsman took the first set in 31 minutes when Dent's return went wide.

Murray took a tumble at the start of the second set having been wrong-footed by a Dent volley as the American took the opening game, but the world number two took charge and he silenced the 23,771 crowd with two bristling return winners to go up a double break before racing to the second set after just 61 minutes.

And he was also comfortable in the third set and secured his place in the last 16 with his second match point, when his lob was called out but he challenged and got the call overturned to secure the victory.