KUALA LUMPUR: Nour El Sherbini interrupted Nicol David's quest for a ninth world crown after winning their quarter-final tie 11-7, 10-12, 11-7, 11-5 at the Naza Women's World Squash Championship in Bukit Jalil today.
Nicol suffered her earliest exit at the World Championship since 2007, when she lost in the second round.
The home favourite's defeat was her fifth in as many meetings with El Sherbini, who advanced to a semi-final meeting with fellow Egyptian Nouran Gohar.
Nicol, who let a 10-7 lead slip in the first game, expressed her disappointment in failing to make her chances count.
"It's tough one and disappointing to lose but had I won that first game it probably would have been a different story," said Nicol, who has yet to make a PSA Tour final this year.
"I just let Nour into the third game and that gave her confidence. I tried doing too much and opened up the court too easily which made her dangerous. I needed to put the pressure on a bit more but I wasn't disciplined as I should have been."
In other quarter-final matches, World No 1 Laura Massaro of England downed Egypt's Omneya Abdel Kawy 11-3, 10-12, 11-8, 11-7 while World No 3 Raneem El Weleily of Egypt ousted American Amanda Sobhy 11-5, 5-11, 12-10, 11-7.
"It was a really tough match today, mentally more than anything else," said El Weleily, runner-up to Nicol at the last world meet in December 2014.
"For some reason I was putting pressure on myself at the start of every game, I lost a few points and that made me lose my confidence and focus. So very happy to win today and to have been tested and come through."
Gohar came through a gruelling encounter with France's Camille Serme 11-7, 12-10, 7-11, 5-11, 11-8 to ensure an Egyptian will play in the final.