Top seed Ana Ivanovic suffered one of the biggest upsets in US Open history on Thursday night, going down 6-3 4-6 6-3 to the unheralded Julie Coin of France.
The 188th-ranked Coin had not played as much as a single match on the WTA Tour prior to this week, but was far from overawed by the occasion as her opponent became the first women's top seed to fall in the second round in the Open era.
Ivanovic came into the final Grand Slam of the season under an injury cloud, having played little since her third round exit at Wimbledon, but nothing could prepare her or the Arthur Ashe Stadium crowd for such a shock.
Coin was the aggressor from the outset and was able to take advantage of Ivanovic's unforced errors, of which there were 34 all told, with eight double faults into the bargain.
The Frenchwoman broke in the seventh game and with a nervous Ivanovic serving to stay in the first set, Coin broke again to take an improbable lead.
She looked set to break again early in the second but the Serbian saved two break points before finding some form, levelling the match and seemingly taking control of the situation.
But the 25-year-old Coin refused to back down, winning 10 points in succession to lead 4-2 in the final set, and although she showed some nerves when double-faulting on her first match point, closed out the match at the third attempt when Ivanovic dumped a forehand wide.
"I really struggled and made too many unforced errors and my serve was not working really well," said Ivanovic, who had been having treatment on a thumb injury. "Obviously, it's very frustrating because I know I can play so much better.
"Obviously if you would ask me at the moment if I'm playing like number one, probably not, but I can't judge too much on that because I really haven't had (a) chance to practice.
"This kind of loss I had today is just incentive to work harder, to go back on the court and to keep working hard and practising and improving."
Coin's reward is a third round date with compatriot Amelie Mauresmo, who battled from a set down to beat Kaia Kanepi of Estonia 2-6 6-4 6-0.

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