French qualifier Julie Coin has claimed the biggest upset in US Open women's history by sending world number one and top seed Ana Ivanovic crashing out in the second round.
Coin, ranked 188th in the world, has beaten Ivanovic 6-3 4-6 6-3, clinching victory on her third match point at Flushing Meadows.
Previously, the top seed at the US Open had not lost earlier than the third round.
"She played completely differently to what I expected," a stunned Ivanovic said after the match.
"She was serving extremely well and hitting very powerful shots.
"I really struggled. I made too many unforced errors and my serve was not working very well.
"She didn't give me options. She was going for her shots.
"Obviously it is very frustrating. I know I can play so much better. This is a very disappointing loss for me."
Twenty-five-year-old Coin, who upset Australia's Casey Dellacqua in the opening round, is making her grand slam debut after successfully coming through the qualifying round.
It has been one of the few upsets in this year's tournament, with most of the seeds again progressing today.
But Ivanovic insists she'll do what it takes to keep her World No.1 mantle.
"This kind of loss I had today is just an incentive to work harder, to go back on the court and keep working hard and practicing and improving because I think I have the possibility to maintain No.1 for a long time and win a grand slam (as No.1)."
Men's seeds James Blake, David Ferrer, Andy Murray, and Stan Wawrinka have all won second round matches today.
While in the women's draw, Dinara Safina, Venus Williams, and Agnieszka Radwanska have all advanced to the third round.
