New York: Britain`s world number 97 Johanna Konta shocked Wimbledon runner-up Garbine Muguruza in the longest women`s match in US Open history on Thursday.
Konta won in 3 hours 23 minutes with her 7-6 (7/4), 6-7 (4/7), 6-2 triumph eclipsing by seven minutes the previous record set in 2011 when Samantha Stosur defeated Nadia Petrova.
"I am so tired. I think both of us were," said Konta, who hit 10 aces and 36 winners in a match played in fierce 30-degree heat.
"She didn`t play her best but she is an incredible fighter and always brings a top-10 mentality.
"I came out to give my best. I was humble enough to know that she could beat me so I fought and chased down every ball."
Sydney-born Konta has now won 15 matches in a row since Wimbledon and goes on to tackle German 18th seed Andrea Petkovic for a place in the last 16.
Muguruza committed 59 unforced errors and had to save 15 of 19 break points.
Ninth seeded Muguruza became the fifth top-10 seed to crash out of this year`s tournament before the third round.
The 21-year-old Spaniard joins first round victims, sixth seed Lucie Safarova, seventh-seeded Ana Ivanovic, number eight Karolina Pliskova and 10th-ranked Carla Suarez Navarro on the sidelines.
With Maria Sharapova having withdrawn through injury on the eve of the season`s concluding Grand Slam, the women`s draw was down to its bare bones.
Top seed Serena Williams and second seed Simona Halep are already in the last 32.
Fourth-ranked Caroline Wozniacki and fifth-seeded Petra Kvitova were in second round action later in the day.Australian 22nd seed Stosur, the last woman to beat Serena Williams at the US Open four years ago when she took the title, breezed past Russia`s Evgeniya Rodina -- one of two mothers to have reached the second round -- 6-1, 6-1.
Stosur, 31, fired eight aces with no double faults and hit 29 winners in her quick-fire win, which gave her a third-round encounter against Italian 16th seed Sara Errani.
Despite the victory, Stosur hit out at organisers, who she claims have blundered over transport for players as well as practice court arrangements.
Stosur said she was forced to switch courts on Wednesday when Williams needed a place to practice.
"She kicked me off my practice court yesterday...so a few issues," said the Australian.
Halep advanced by defeating Ukraine`s 104th-ranked Kateryna Bondarenko 6-3, 6-4.
"It was a tough match. She was playing really well. She came after two years` break and she was amazing," said Halep of her opponent, who was playing in New York for the first time since 2012 after having had a baby.
The 23-year-old Halep will next face either Japan`s Karumi Nara or American Shelby Rogers.
Victoria Azarenka, seeded at 20 and the 2012 and 2013 runner-up to Williams, also made the last 32.
The Belarusian, playing in just her 13th tournament of an injury-hit season, saw off 2009 semi-finalist Yanina Wickmayer of Belgium, 7-5, 6-4.
"She doesn`t give you much time. She came out firing and I had to fight and dig deep," said the 26-year-old.
Errani made the next stage by seeing off Latvian qualifier Jelena Ostapenko 0-6, 6-4, 6-3 with Petkovic defeating Russia`s Elena Vesnina 6-3, 7-6 (7/4).
Later Thursday, five-time champion Roger Federer and 2012 winner Andy Murray head the line-up on while 2001 champion Lleyton Hewitt could play his final match at the tournament.
World number two Federer, who reigned supreme in New York from 2004-2008 and was runner-up in 2009, faces Belgium`s Steve Darcis, the man who dumped Rafael Nadal out of Wimbledon in the first round in 2013.
Federer, 34, bidding to become the oldest men`s champion since Ken Rosewall in 1970 and clinch an 18th major, breezed through his opener against Leonardo Mayer in just 77 minutes on Monday.
Murray, the third seed, got past controversial Australian Nick Kyrgios in four sets in his first round.
The 28-year-old Scotsman takes on French world number 35 Adrian Mannarino, a left-hander who has twice made the third round.
Murray won their only other previous meeting at Indian Wells this year in straight sets.
Hewitt, who made his New York bow in 1999, faces fellow Australian and Davis Cup teammate Bernard Tomic, the 24th seed.
It will be Hewitt`s 60th and last career match at the tournament if he loses, as he has already announced he will retire after next year`s Australian Open.
Also in action Thursday is Swiss fifth seed and French Open champion Stan Wawrinka, who faces South Korean teenager Hyeon Chung.