Less than two weeks after losing to Nick Matthew in the World Open final in Rotterdam, Frenchman Gregory Gaultier earned his revenge in Hong Kong today by upsetting the world number one from England in a 90-minute marathon in the quarter-finals of the Cathay Pacific Sun Hung Kai Financial Hong Kong Open, the seventh PSA World Series squash event of the year.

While Gaultier was 9-7 ahead in their Tour career head-to-head tally, Matthew had won their three most recent encounters - and looked in commanding form today as he took the opening game.

The fifth seed came back to take the second but again Matthew seemed to have the upper-hand as he built up a 9-4 lead in the third.

But the dynamic of the match changed at that point as the Frenchman mounted a massive comeback to take the game after a tie-break - before romping ahead in the fourth and ultimately closing out the match 7-11, 11-9, 13-11, 11-5.

"I think we were both tired today, everybody knows that we were playing in the final of the Worlds last week, and that I lost," Gaultier told www.squashsite.com afterwards. "So today, I was dying for revenge.

"In the third, it was a toss of a coin! I was 9-4 down, and I thought, well, win or lose, I'm just going to make him work for it. And point by point, I dug in. At 7-8, 8-9, I realised that I could actually win that game. And of course, when I did, it was a great advantage for me, 2/1 up," continued the 28-year-old from Aix-en-Provence - now just one match away from his fifth final appearance in a row.

The world No5 will now play life-long European rival James Willstrop, the world No3 from England who was gifted his place in the semi-finals when his England team-mate opponent Peter Barker was forced to withdraw with an injury early in the third game.

"I really feel for him," said Willstrop after his 27-minute encounter. "But you can't take any risks when it comes to the knee and you can't play squash if you can't run."

Gaultier is aware of the advantage Willstrop has over him after their contrasting quarter-final clashes: "I've watched James play today, he looks sharp. So now, no celebration, just my normal routine, to get ready for tomorrow. I know James didn't have a long match as Peter got injured, so it will be a bit of a challenge. But then again, I love challenges!"

There was a further significant upset in the other half of the draw when Malaysia's Mohd Azlan Iskandar became the only unseeded player to make the semi-finals after beating Egypt's fourth seed and four-time Hong Kong Open champion Amr Shabana 11-9, 11-5, 11-6.

The 29-year-old from Kuala Lumpur has enjoyed a fine run of form in Hong Kong, which began with a four-game win over Egypt's seventh seed Mohamed El Shorbagy. Iskandar is now in his first PSA World Series semi-final of the year - and certain to finish in the top eight of the 2011 World Series standings after the completion of the event.

"I don't think Shabana was at his best today, but I'll take it," said the delighted winner. "My first semi in Hong Kong!"

Iskandar will face Karim Darwish, the No2 seed from Egypt who ended unseeded Australian Stewart Boswell's run 11-5, 11-4, 11-6.

"Overall, happy with my performance," said the 30-year-old from Cairo, now in his third successive Hong Kong semi-final. "Last time I played Azlan was in the US Open, I was not 100% at my best, but normally, we have great matches. He is a good mate and a fair player. I'm looking forward to it."

RESULTS: PSA World Series Cathay Pacific Sun Hung Kai Financial Hong Kong Open, Hong Kong

Quarter-finals:
[5] Gregory Gaultier (FRA) bt [1] Nick Matthew (ENG) 7-11, 11-9, 13-11, 11-5 (90m)
[3] James Willstrop (ENG) bt [6] Peter Barker (ENG) 11-3, 11-8, 3-0 ret. (27m)
Mohd Azlan Iskandar (MAS) bt [4] Amr Shabana (EGY) 11-9, 11-5, 11-6 (40m)
[2] Karim Darwish (EGY) bt Stewart Boswell (AUS) 11-5, 11-4, 11-6 (39m)

Semi-final line-up:
[5] Gregory Gaultier (FRA) v [3] James Willstrop (ENG)
[2] Karim Darwish (EGY) v Mohd Azlan Iskandar (MAS)

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