Djokovic storms into US Open last 16

Defending champion Novak Djokovic stormed into the US Open last 16 as Andy Roddick stretched his long goodbye into a prime-time showdown with fellow former champion Juan Martin Del Potro. Djokovic coasted past French 30th seed Julien Benneteau 6-3, 6-2, 6-2 despite being forced to open up play on day seven at Arthur Ashe Stadium. "It was an early match for me. Usually I don't like to play the first match," said second-seeded Djokovic. "So it was important to stay strong and commit to every point." In stark contrast, Sunday's programme finished at 2.26 a.m. on Monday morning (06:26 GMT), equalling the latest-ever finish for the tournament. That was the time when German 19th seed Philipp Kohlschreiber completed his 6-4, 3-6, 4-6, 6-3, 6-4 win over US ninth seed John Isner. Djokovic didn't face a single break point in his 97-minute victory, his fourth on the trot against Benneteau, firing 13 aces and 41 winners. The 25-year-old hasn't dropped serve since the first game of his first-round match and has made the last 16 for a sixth successive year by losing just 14 games in three rounds. He goes on to face Swiss 18th seed Stanislas Wawrinka, a semi-finalist in 2010 who eased past 14th-seeded Ukrainian Alexandr Dolgopolov 6-4, 6-4, 6-2 for a spot in the quarter-finals. American 20th seed Roddick delayed his retirement by advancing to the fourth round with a 7-5, 7-6 (7/1), 4-6, 6-4 victory over Italy's Fabio Fognini. Roddick, the 2003 US Open winner who will retire once this tournament is over, will play for a spot in the quarter-finals against 2009 winner Juan Martin Del Potro, the seventh seed from Argentina. "I am trying to keep all of my emotions together. All the support I have received over the past few days has been truly humbling," said 30-year-old Roddick. Del Potro defeated 63rd-ranked compatriot Leonardo Mayer 6-3, 7-5, 7-6 (11/9) in a three-hour 20-minute marathon which was wrapped up on his sixth match point. Del Potro's win in New York three years ago was the only occasion in the last 30 majors that the champion wasn't Roger Federer, Rafael Nadal or Djokovic. "It's not easy when you are playing another Argentinian and a guy who is a friend. He makes a lot of first serves and plays serve-and-volley," said Del Potro. "This is my best tournament. All of my biggest memories are here." While Roddick survived, another former champion, 2001 winner Lleyton Hewitt, was knocked out by low-profile Spanish fourth seed David Ferrer, a semi-finalist in 2007, who clinched a 7-6 (11/9), 4-6, 6-3, 6-0 win. Former world number one Hewitt, who has not reached the last 16 at the US Open since 2006, and has been plagued by groin and foot problems this year, committed 72 unforced errors and squandered five set points in the first set tie-breaker. "All in all, I'm happy. It takes a quality player to beat me," said 31-year-old Hewitt, who needed a wildcard to play in New York after his ranking slumped to 125. Ferrer, a semi-finalist already this year at the French Open, and a quarter-finalist at the Australian Open and Wimbledon, has five titles to his name in 2012 -- second only to world number one Federer. "I'm having the best season of my career and I think it's the right time. I'm 30 years old," said Ferrer, who will next face French 13th seed Richard Gasquet. Gasquet beat 245-ranked US college champion Steve Johnson 7-6 (7/4), 6-2, 6-3. Hewitt, 31, and Ferrer were two of eight players 30-or-older to reach the third round, the most since 1974. Serb eighth seed Janko Tipsarevic, a quarter-finalist in 2011, made the last 16, beating Slovenian qualifier Grega Zemlja 6-4, 6-3, 7-5 and will now face Kohlschreiber for a quarter-final spot.