It was David's fourth loss in five matches to El Sherbini, who will meet either compatriot Nouran Gohar or Camille Serme, the defending champion from France, in Sunday's final.

The fourth-seeded Egyptian beat the world champion 11-6, 2-11, 11-9, 11-5, with a flawed but aggressively impressive performance which suggested she could soon be the next to grab a frequently changing top ranking.

David lost that last year to Raneem El Welily, while the current number one, England's Laura Massaro, was beaten in Friday's quarter-finals.

David showed many signs of producing a more creative and varied short game and led 8-5 in the third game, at which stage it seemed quite possible she would atone for losses to El Sherbini in Qatar, New York and Chicago.

"I started to relax and to win a few outright winners, but when I stepped back slightly she just took her chances," the 32-year-old David said.

"But I am fine tuning and adjusting my game, and I need to do that and be a consistent as possible. With the top four, when they see a window they will take it. It's a question of closing that window as much as possible and finding space they are giving me as well."

David will hope to do that in the short time available before defending her world title in Kuala Lumpur next month, but in the meantime there is little doubt that El Sherbini is beginning to establish a dominance.

It has taken four years for her to reach a British Open final again after her 2012 loss to David, and the crux of her success was her reaction to David's rapid capture of the second game.

She scored winner after winner with sudden angled boasts combined with clever drops, but El Sherbini was able to keep the ball tighter and deeper and lengthen the rallies again.

The Egyptian also found a good length drive and a volley drop to end a losing four-point sequence in the third game, and followed it with a heavy forehand drive winner and a forehand kill to get back to parity at 8-8.

The two mistakes which David made in the two rallies after that did much to allow the contect to swing back the Egyptian's way.
In the fourth game El Sherbini's confidence rose and she was soon 6-1 up although David fought well and kept her hopes alive till the end.

"Since I reached the final (of the British Open) I have been trying to make it again," said El Sherbini.

"Nicol has always been very tough from the beginning every time I have played her, and I knew I had to give everything from the start.

"In the third game (when trailing 5-8) I had nothing to lose, and I just had to go for it, and that gave me some confidence again. You have to go for it. I am trying to play perfect shots at the perfect time."

Sherbini's win increased the chances that Egypt can win both women's and men's titles for the first time.