Egypt's Mohamed El-Shorbagy, the world’s number one squash player, lost to world number 24 and former world number one, Englishman James Willstrop, in the third round of the 2015 Men's World Championship.

The 24-year-old squash star quit the tournament after losing 3-1 to Willstrop with 11-4, 11-7, 10-12, 11-7 in 61 minutes.

Top seed El-Shorbagy has so far failed to secure the World Championship title losing out to fellow Egyptian Ramy Ashour in both the 2012 and 2014 finals.

"Bad days in the office can happen but I do hate it when it happens in big tournaments!!" El-Shorbagy wrote on his Twitter account after the game.

"Good to see James back at his best though," the world number one added.

"But one thing I know for sure....I will be back," he concluded.

Mohamed El-Shorbagy's brother, Marwan El-Shorbagy, who is world number nine, lost to Englishman Nick Matthew 3-0 with 13-11, 12-10, 11-5 in 53 minutes.

However, four other Egyptian players made the last eight at the 2015 Men's World Championship with Ali Farag, the world number 33, defeating the world number 7, Germany's Simon Rosner, 3-1 at 7-11, 13-11, 11-6, 11-9 in 77 minutes.

"Simon is such a great player, he beat me in the US Open, so to get my revenge here is unbelievable… Oh whaoooo, oh whaoooo, I feel… I have no word… 7th Heaven," Farag wrote on social media after the game.

"I was lucky at the start when we have the injury break to have Hossam to stop the bleeding, and Shabana for the mental side, he helped me to stay focused, he told me how he dealt with those situations, and it really helped me," the Egyptian player added.

The 23-year-old will face world number three Gregory Gaultier of France in the final eight of the tournament on Friday.

Ramy Ashour, the world number four, also defeated his countryman Karim Abdel Gawad 3-1 with 11-6, 12-10, 8-11, 11-7 in 54 minutes to book a place in the last eight.

"About Mohamed losing, I have so much in my mind I cannot handle any more, it’s just crazy, I just glad that the energy of the upset didn’t get to me," said Ashour about Mohamed El-Shorbagy's loss.

"I can only say there is no guarantee, that’s my favourite quote, anyone can beat anyone on the day," he added.

The three-time world championship winner will face world number seven Omar Mosaad, who is also Egyptian, in the final eight, also on Friday.

Tarek Momen, the world number eight, also booked his place among the last eight after beating Frenchman Gregoire Marche 3-1 with 7-11, 11-3, 11-3, 11-7 in 55 minutes.

The 27-year-old squash star Momen will face Englishman Nick Matthew, the world number two, in the last eight, also on Friday.

"It’s my first time ever in the quarters," Momen said after the game.

"You have no idea how happy I am to play the way I played. You have no idea, truly, because I went through a lot, and even in the match against Joe Lee," he added.

The 2015 World Championships started on 13 November with the first qualifying round and will finish on 22 November.

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