2nd round (top half of draw):
 Nicol David (MAS) bt  Camille Serme (FRA) 11-9, 11-5, 11-4 (36m)
 Madeline Perry (IRL) bt  Line Hansen (DEN) 6-11, 11-2, 11-3, 11-8 (41m)
 Alison Waters (ENG) bt  Donna Urquhart (AUS) 8-11, 11-5, 11-6, 9-11, 12-10 (58m)
 Joelle King (NZL) bt  Sarah Kippax (ENG) 11-9, 11-4, 11-7 (31m)
England's Alison Waters admitted that it was a 'patchy' performance that saw the fourth seed survive her second round encounter with Australia's Donna Urquhart in the Women's Delaware Investments U.S. Open Championship, the Women's Squash Association World Series Platinum event which - for the first time ever - is providing equal prize money to the men's event.
Waters, the world No4, went into the match at Drexel University in Philadelphia boasting a 4/1 career head-to-head record over the left-hander from New South Wales, ranked 21 places lower.
But the Londoner squandered an 8-3 lead in the opening game to allow Urquhart to win the next eight points in a row to take an unlikely one game lead. Waters upped her game to take the next two to go 2/1 up - but Urquhart came out firing in the fourth to level the match.
Waters (pictured above in action with Urquhart) took early leads in the decider - but the Australian underdog drew level at seven-all. Two careless tins from the Englishwoman put Urquhart within two points of the match - but three crisp winners later gave Waters match-ball at 10-9.
A stroke saw Urquhart draw level at 10-all - but Waters converted her next match-ball to finally secure her 8-11, 11-5, 11-6, 9-11, 12-10 win after 58 minutes.
"Donna played well, but I was pretty patchy throughout," admitted Waters. "I'm just glad to have got through!"
Waters now faces fifth seed Joelle King, the world No5 from New Zealand who defeated England's Sarah Kippax 11-9, 11-4, 11-7.
"I had a close match against Nouran (Gohar) in the first round, and that was probably just the kick up the bum I needed," admitted 25-year-old King afterwards. "I'm glad I was able to come out and play much better today, even if I did make a few errors at the start."
Favourite Nicol David maintained her 'clean sheet' in the event by beating Camille Serme 11-9, 11-5, 11-4 in a repeat of her victory over the fast-improving French number one in last week's Carol Weymuller Open final in New York.
"I was really pumped up for this, ready to give my best," said the world number one from Malaysia (pictured above in action with Serme) after extending her career head-to-head record over world No10 Serme to 10-0.
"We played last week and she was playing really well, so I knew she would be fired up for it. I managed to settle and get into my game but it wasn't easy, she played well again."
David, bidding to become the first player to defend the title for over 20 years, now meets Irish rival Madeline Perry, the No8 seed from Belfast who recovered from a game down to beat Dane Line Hansen 6-11, 11-2, 11-3, 11-8 in 41 minutes.
"She started well, her length was better than mine and I just couldn't get control of any rallies," said Perry, the 36-year-old world No9. "But I felt much better from the start of the second.
"I've been struggling with a knee injury for the last couple of months, so it's just nice to be playing again. I'm looking forward to the quarter-finals and having another rest day can't hurt!"
Event website: www.usopensquash.com
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photo Getty Images