Determined former world number one Karim Darwish saw off 20-year-old fellow Egyptian Mohamed El Shorbagy in tonight's final pool round of the ATCO PSA World Series Squash Finals in London to clinch the last semi-final slot in the flagship PSA World Tour event at The Queen's Club.

The $110,000 championship features the eight players who earned the most points from the nine PSA World Series championships in 2011.

Darwish, who boasted a 4/1 Tour head-to-head record over his young Egyptian team-mate, was also after revenge as El Shorbagy won their last clash, in December's PSA Masters in India.

The young pretender, ranked a career-high six in the world, led in both games - but experienced campaigner Darwish, the world No5, rose to the challenge and clinched an 11-9, 11-9 victory after 40 minutes.

The win puts the 30-year-old from Cairo into second place in Group 1, and a third appearance in the event's semi-finals since 2007.

"Mohamed beat me last time so it was good beat him this time round," said Darwish afterwards. "I had to play 100% to get my revenge. He's a great player, only 20 years old - I think he'll be at the top one day.

"I'm just happy to be in the semi-final of such a prestigious event."

With two victories already behind him, England's James Willstrop had already secured a place in the last four - and top place in Group 1.

But the newly-crowned world number one suffered a minor set-back with a shock defeat to Malaysia's Mohd Azlan Iskandar.

With title victories in three successive PSA World Series events at the end of last year, Willstrop was expected to extend his career-best 17 match unbeaten run.

But Iskandar threw everything he had at the match and finally emerged the 11-6, 6-11, 11-9 victor after 41 minutes.

"I don't think James was on top of his game, possibly thinking about tomorrow's semi-finals," suggested the world No10 from Kuala Lumpur. "It gives me some redemption and I'm happy to get the win."

Later, Frenchman Gregory Gaultier became the only player to register three wins out of three when he defeated Egypt's four-time world champion Amr Shabana 11-7, 11-4 in just 20 minutes.

"It wasn't easy," said the 29-year-old from Aix-en-Provence afterwards. "I've had to give a big push as this game is always unpredictable."

The Group 2 winner will now face Darwish for a place in the final. "Tomorrow's game against Karim will be a tough battle. We know each other well so I am looking forward to it and will be doing my best to stay focussed," added Gaultier, the 2008 and 2009 champion.

Shabana finished as runner-up in the Group and takes on Willstrop in the other semi.

The other final pool match in the group saw England's Peter Barker record his first win in the event, stemming a fightback by Laurens Jan Anjema to beat the Dutchman 11-8, 9-11, 11-9 in 51 minutes.

RESULTS: ATCO PSA World Series Squash Finals, London, England

3rd & final pool round:

Group 1:
[6] Mohd Azlan Iskandar (MAS) bt [1] James Willstrop (ENG) 11-6, 6-11, 11-9 (41m)
[3] Karim Darwish (EGY) bt [7] Mohamed El Shorbagy (EGY) 11-9, 11-9 (40m)

Group 2:
[5] Peter Barker (ENG) bt [8] Laurens Jan Anjema (NED) 11-8, 9-11, 11-9 (51m)
[2] Gregory Gaultier (FRA) bt [4] Amr Shabana (EGY) 11-7, 11-4 (20m)

Semi-final line-up:
[1] James Willstrop (ENG) v [4] Amr Shabana (EGY)
[2] Gregory Gaultier (FRA) v [3] Karim Darwish (EGY)

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