KUALA LUMPUR: Hong Kong's Annie Au produced the biggest shock of the US Open in Philadelphia on Monday by sending eight-time world champion Nicol David crashing out in the second round.
Au, who had not beaten Nicol in 23 prior career meetings, recovered from blowing a two-game lead to down the three-time US Open winner 11-5, 11-5, 10-12, 8-11, 11-7 in 56 minutes.
It was World No 6 Nicol's second defeat to a player from Hong Kong this year after going down to Joey Chan at the World Games in Poland in July.
"To beat Nicol in my first ever win on the glass court at this event is a massive result and makes all the hard work over the summer feel worth it," said World No 9 Au, who goes on to meet England's Laura Massaro in the quarter-finals.
Nicol, who won the US Open from 2012 to 2014, was a runner-up at the Netsuite Open in San Francisco just a week ago, and this exit leaves the 34-year-old with just the Ciudad de Floridablance title, won in Colombia in March, to her name in the past 21 months.