NEW YORK (AP) Didn't take too long to see that Novak Djokovic's right shoulder is feeling fine.
Which was good, because he was on court for less than an hour Tuesday.
He began his first-round match at the U.S. Open with a 121 mph service winner. Four points later, he closed that game with a 120 mph ace. He whipped forehands exactly where he wanted them. He returned well, too.
Playing his first match since Aug. 21, when he quit because of a sore and tired shoulder, the top-seeded Djokovic began setting aside any questions about his fitness for Flushing Meadows, building a 6-0, 5-1 lead before qualifier Conor Niland of Ireland stopped after 44 minutes. Niland had food poisoning.
Great opening performance,'' Djokovic declared.Today I didn't feel any pain. I served well, and I played well, so I have no concern.''
He improved to 58-2 with nine titles in 2011, including at Wimbledon and the Australian Open, allowing the 24-year-old Serb to overtake Rafael Nadal - the defending U.S. Open champion who played his first-round match Tuesday night - atop the rankings. Djokovic is on his way to compiling one of the greatest seasons in tennis history, particularly if he can earn his first championship at the U.S. Open, where in the past four years he's lost twice in the final and twice in the semifinals.
``This year has been tremendous - best so far in my career - and there has been a lot of talk about history-making and this incredible run,'' Djokovic said.
His showing Tuesday was the most noteworthy development in the men's draw during an afternoon session that included a second consecutive first-round departure from the U.S. Open by the sixth-seeded French Open champion Li Na. Since becoming China's first major singles champion at Paris in June, Li has gone 5-6, exiting in the second round at Wimbledon, then losing 6-2, 7-5 to 53rd-ranked Simona Halep of Romania on Tuesday.
Terrible feeling,'' Li said.I really want to do well after Roland Garros. But, I mean, it's not easy to do. Always easy to say, 'I want to do, I would like to do,' but always lose early. Now I even lose all the confidence on the court. I was feeling, 'Oh, tennis just too tough for me.'''
It's the first time in 40 years that none of the women's champions at a season's first three Grand Slam tournaments reached the second round at the U.S. Open. Wimbledon champion Petra Kvitova lost her first-round match Monday, while Australian Open champion Kim Clijsters withdrew because of a stomach muscle injury.
The active leader for women's Grand Slam titles, Serena Williams, was to follow Nadal in Arthur Ashe Stadium on Tuesday night.
Earlier, top-seeded Caroline Wozniacki - who's been ranked No. 1 for most of the past year but is still in search of Grand Slam trophy No. 1 - defeated 125th-ranked Nuria Llagostera Vives of Spain 6-3, 6-1.
Afterward, Wozniacki was asked about criticisms that she lacks a big-time shot.
They can say what they want,'' said Wozniacki, who is dating U.S. Open golf champion Rory McIlroy.I'm the type of player I am.''
Among the past major winners who advanced Tuesday were 2010 French Open champion Francesca Schiavone, who overcame 16 double-faults, including four in her last service game; 2008 French Open champion Ana Ivanovic, whose blood pressure was checked by a trainer at the final changeover and said afterward she felt overwhelmed while thinking about the recent death of her grandfather; and two-time Grand Slam champion Svetlana Kuznetsova.
Other winners included No. 4 Victoria Azarenka, No. 10 Andrea Petkovic, No. 11 Jelena Jankovic and three young Americans: Sloane Stephens, CoCo Vandeweghe and Vania King.
Two seeded men lost during the day: No. 16 Mikhail Youzhny was beaten by Ernests Gulbis of Latvia 6-2, 6-4, 6-4, and No. 32 Ivan Dodig was eliminated 6-7 (6), 6-3, 6-0, 2-6, 6-2 by Nikolay Davydenko of Russia, who was a U.S. Open semifinalist in 2006 and 2007 and once was ranked No. 3 but now is 39th.
Winners included No. 5 David Ferrer, No. 11 Jo-Wilfried Tsonga, No. 17 Jurgen Melzer and Americans James Blake and Donald Young.
Tsonga's next opponent is Sergei Bubka, the son of the pole-vault world record-holder of the same name, who is a qualifier ranked 207th and won his first Grand Slam match Tuesday.
Bubka and Djokovic are the same age and both live in Monte Carlo, so they have practiced together on occasion. Djokovic didn't do much in the way of hitting tennis balls in the time since he decided he couldn't continue while trailing in the second set of the Cincinnati Masters final against Andy Murray.
Throughout the whole week I was carrying the pain and discomfort in my shoulder,'' Djokovic said.After Cincinnati, I took some time off. I did everything to recover the shoulder.''
Against Niland, Djokovic won the first seven games. After Niland finally got on the scoreboard, Djokovic took the last 16 points they played.
As well as Djokovic played, the 197th-ranked Niland - no man representing Ireland played at the U.S. Open in the Open era until this year - wasn't able to provide much resistance after whatever caused him problems at dinner Sunday night.
We're thinking it was either salad or a pork dish,'' Niland said.We're not giving away the name of the restaurant.''
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