World champion Karim Gawad was prevented from achieving the world number one ranking for the first time in his career when he lost to his best friend in the second round of the British Open on Thursday.
Gawad was beaten 6-11, 12-10, 11-9, 11-7 by Mohamed Abouelghar, the world number 23 with whom he is rooming, just when he was on the brink of climbing to the summit.
The man from Cairo was twice within a point of going two games up before being blown away by a display of uninhibited hitting by Abouelghar, who has rarely managed to maintain such exceptional standards against a top level opponent for so long.
Although suffering from a cold, Gawad often played very well himself, recovering from 3-8 to 9-9 in the third game, and from 0-4 to 7-8 in the fourth.
He also tenaciously continued the struggle despite two falls, a three-minute injury break and broken strings in a racquet.
But Abouelghar finished the match with a blaze of four unstoppable winners and then explained why he had thought he had a chance of beating his far better known friend.
"I knew that the ranking situation put him under pressure, and so I just went for my shots," he said. "When I do that sometimes it works and sometimes it doesn't. Today it did.
"I have mixed feelings about it. I really wanted him to take it (the number one ranking) and I know how had he works. I just played for myself, and I had no pressure."
The upset means that a third Egyptian, Mohamed Elshorbagy, can still hang on to the world number one ranking he has held for 28 months, 15 of them consecutively, if he wins the British Open for a third successive time on Sunday.
However Gregory Gaultier can also regain the top spot if he wins the title.
The only Frenchman ever to have won the British Open, he signalled an enduring capacity to win it again with a devastating 9-1, 9-3, 9-2 over Cameron Pilley, the World Series finals runner-up.
Gaultier, 34, on Friday plays Mathieu Castagnet, his unseeded compatriot, while Elshorbagy plays Ali Farag, his seventh-seeded Egyptian compatriot
Earlier squash legend Nicol David also reached the quarter-finals and refuted suggestions that she might be retiring some time soon.
The 33-year-old record-breaking former world number one from Malaysia beat Joey Chan, the world number 17 from Hong Kong, 11-4, 14-12, 9-11, 11-2 and afterwards made it clear that her motivation was as great as ever.
"I still love it passionately and deeply, and I will play as long as I can," she said.
"If I wake up and still feel like doing it, I will do it," said David, who went more than a year without a title until she triumphed in Colombia a fortnight ago.