Annie Au of Hong Kong became the first Chinese player into the quarter-finals of a major tournament when she made a tremendous comeback from two games down in the British Open on Wednesday.

Au overcame Alison Waters, the former world number three from England by 9-11, 7-11, 11-9, 11-9, 11-7 in an hour-long tussle during which she was behind for most of the time and twice within two points of defeat.

It meant that the seventh-seeded Au had produced one of the best performances of her career in a platinum World Series event which is the richest on the WSA tour outside the World Open.

It also raised hopes that the success of Au Wing Chi, to give her Chinese name, may help stimulate the spread of squash on the Chinese mainland, even though it is a very long way from the popularity of badminton or table tennis - nor yet has the growth potential of tennis since Li Na's success.

But Au was intelligent and focused, had a good game plan and stuck to it, and was good enough to overcome an opponent almost back to her best after a long spell on the sidelines with injury.

"I was a little bit nervous and had to warm up longer. There is a lot of cheering and a good atmosphere and I had to adapt," said Au, speaking of the change from conventional club courts, in a first round win over Gaby Huber of Switzerland, to the shining all-glass show court in London's O2 arena.

"I just had to be patient to keep to what I knew was working, because sometimes I'm not patient enough," said a smiling Au, who slowed the pace down in the last three games, and kept the ball to the back relentlessly before attempting anything creative.

She had to survive two crises. Waters, attacking hard whenever there was a slight chance, got back from 7-9 to 9-9 in the third game, and then repeated this recovery in the fourth.

Au escaped the first time with a long sequence of straight forehand wall-clingers on a side of the court where reflections in the glass made it harder to see, and more difficult for Waters to volley.

And on the second occasion Au wriggled to safety with a little luck when she was donated a penalty stroke from a Waters mishit. She then immediately leveled at two games all with a great drop-lob-drop shot sequence.

In the fifth game she soon took a five-point lead and advanced steadily to victory against a Waters who may have been tiring after her five-game match against Malaysia's Low Wee Wern the day before.

"I'm really pleased," said Au, though she already seemed to have half a mind on getting ready for the next encounter.

That will be against Nour El Sherbini, the 16-year-old Egyptian prodigy, who won her second successive five-game match.

Sherbini overcame Madeline Perry, the fourth seeded Irishwoman who was British Open runner-up last time, three years ago, by 11-6, 4-11, 5-11, 11-3, 11-5.