Caroline Wozniacki of Denmark returns a shot to Svetlana Kuznetsova of Russia during the second round women's singles match of the 2016 US Open. (Andy Lyons/Getty Images/AFP) |
Top see Djokovic was handed a walkover when Jiri Vesely of the Czech Republic withdrew from their second round encounter suffering an inflammation of the left forearm.
Vesely's misfortune was a welcome boost for top seed Djokovic who had required treatment on his upper right arm in his laboured first round win over Jerzy Janowicz on Monday.
Left-hander Vesely had defeated the Serb at the Monte Carlo Masters in April.
Djokovic will face either Guido Pella of Argentina or Mikhail Youzhny of Russia on Friday for a place in the last 16.
"I'm very, very disappointed right now," said 23-year-old Vesely who was also forced to pull out of his quarter-final in Winston-Salem last week with the same injury. "I was looking forward to playing Novak, I would have nothing to lose."
Wozniacki, the runner-up in New York in 2009 and 2014 but who has slipped to 74 in the world after a season decimated by a right ankle injury, defeated 2004 champion Svetlana Kuznetsova 6-4, 6-4.
The 26-year-old Dane recovered from 0-4 down in the first set to record a seventh win in eight meetings and third in New York over the ninth-seeded Russian.
"I stopped looking at the world rankings when I dropped out of the top 10," said Wozniacki when asked how she kept her spirits up during her recent slump.
Next up for Wozniacki is Romania's Monica Niculescu.
Seventh seeded Italian Roberta Vinci, defeated by compatriot Flavia Pennetta in last year's final, eased past Christina McHale of the United States 6-1, 6-3.
The 33-year-old, playing at Flushing Meadows for the 14th time, goes on to face Germany's Carina Witthoeft.
NADAL EYES LAST 32
"It's nice of course to come back but you have a lot of pressure," said Vinci who was ranked 43 in the world this time last year.
"Now I'm seven in the world - a lot of points to defend. But probably the key is don't think about this."
Slovak 12th seed Dominika Cibulkova overcame a left-thigh injury to see off Russia's Evgeniya Rodina 6-7, 6-2, 6-2, winning 17 of the last 18 points.
Two-time Wimbledon winner Petra Kvitova, the 14th seeded Czech who recorded her best performance in New York 12 months ago when she made the last-eight, beat Turkey's Cagla Buyukakcay 7-6 (7/2), 6-3.
Kvitova was in her trademark all-or-nothing mood, mixing up 31 winners with 30 unforced errors against her 26-year-old opponent.
"If I make the second week, I'll be happy," said Kvitova, keen to dampen down expectations.
Kvitova now plays Ukrainian 22nd seed Elina Svitolina who put out Lauren Davis of the United States 6-1, 4-6, 6-3.
South Africa's Kevin Anderson saw off Canada's Vasek Pospisil 7-6 (7/3), 6-4, 6-4.
Anderson reached the quarter-finals last year, beating 2012 champion Andy Murray on the way, but has been plagued by knee, shoulder and ankle injuries in 2016 which forced him to skip eight events.
Britain's Kyle Edmund backed up his first round win over world number 15 Richard Gasquet with a 7-5, 6-4, 6-4 victory over US wildcard Ernesto Escobedo.
John Inser of the United States fired 38 aces to beat Belgian qualifier Steve Darcis 6-3, 6-4, 6-7 (10/12), 6-3 and next faces Edmund.
Later Wednesday, Spanish fourth seed Rafael Nadal, the 2010 and 2013 champion, takes a 7-1 career record over Italy's Andreas Seppi into their night time clash.
Reigning Roland Garros champion and third seed Garbine Muguruza of Spain tackles Latvia's Anastasija Sevastova.
Muguruza needed three sets to see off Belgian qualifier Elise Mertens in a first round tie which also saw her need a medical timeout after suffering heat exhaustion.
Angelique Kerber, the second seeded Australian Open champion who could depose Serena Williams as world number one, faces 34-year-old Mirjana Lucic-Baroni.
The veteran Croatian made the last 16 in 2014 having played her first US Open back in 1997.
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