Malaysia's Mohd Azlan Iskandar produced the upset of the day in today's second round of the Cathay Pacific Sun Hung Kai Financial Hong Kong Open when he downed in-form Egyptian Mohamed El Shorbagy, the No7 seed, to secure an unexpected place in the quarter-finals of the seventh PSA World Series squash event of the year.

El Shorbagy, the 20-year-old world No8 from Alexandria, arrived in Hong Kong fresh from title success in last week's PSA International 50 Macau Open. The Egyptian, who went into the match 3/0 ahead in his head-to-head tally with Iskandar, took the opening game.

But the 29-year-old Malaysian, the world No13 from Kuala Lumpur, recovered to win 6-11, 11-6, 14-12, 11-7 and claim an impressive first win over his higher-ranked opponent in 56 minutes.

And there will be a surprise Australian name in the last eight line-up after unseeded Stewart Boswell beat England's Tom Richards 11-4, 11-9, 11-0 in 42 minutes.

The 33-year-old former world No4 from Canberra is enjoying some of the best form of his recent career: After previously making the last eight of a PSA World Series event in January 2008, Boswell burst through to the semi-finals of last month's Qatar Classic - and now, after making his Hong Kong breakthrough by beating No8 seed Thierry Lincou in the opening round, is through to his second successive quarter-final.

"When I looked at the draw, I didn't think I was that lucky, but it turned out to be good after all," Boswell told afterwards. "I think I was again a bit lucky, like I was in Qatar. But then, yet again, I still had to play my best squash to win today."

In Lincou's unexpected absence, French interest in the quarter-finals will be led by fifth seed Gregory Gaultier, the recent Qatar Classic champion who was stretched to four games before overcoming Egypt's Omar Mosaad 11-6, 4-11, 11-4, 11-6.

The day otherwise belonged to Englishmen and Egyptians - with England team-mates Nick Matthew, Peter Barker and James Willstrop coming through in the top half of the draw, and Cairo compatriots Amr Shabana and Karim Darwish prevailing in the other half.

Barker continues to be the most consistent performer in the 2011 PSA World Series by claiming his seventh quarter-final berth in a row. In a repeat of his victory over Cameron Pilley in the World Open earlier in the month, the London left-hander again despatched the Australian in straight games, winning 11-8, 11-7, 11-4 in 47 minutes.

"After my first round I had to be more ruthless," said the sixth seed. "And I think that tactically, I played well today. In Rotterdam, the court suited me better, and it was easier for me. But today, the court was more suited to his game, in particular his forehand, and I had to be prepared to be more proactive. And I was.

"I'm really happy with the way I played. I was trying to frustrate him, and only he can say if I succeeded, but I'm happy with what I implanted."

Matthew defeated fellow countryman Daryl Selby 12-10, 11-7, 11-8 in 65 minutes.

"I enjoyed my match today," said Selby later on Twitter. "Not the losing part but the running around like a maniac part. Disappointed, but Nick Matthew was a warrior!"

Willstrop eased into his sixth World Series quarter-final of the year after defeating Finland's Olli Tuominen 11-3, 11-8, 11-6.

Fourth seed Shabana, looking for his sixth title in Hong Kong after following his World Open success there in 2005 by four successive Hong Kong Open title triumphs, beat fellow countryman Hisham Mohamed Ashour 11-5, 11-7, 12-10, while in the final match of the day second seed Karim Darwish ended Tarek Momen's great run by beating the Egyptian qualifier 11-3, 11-2, 5-11, 11-7.

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

2nd round:
[1] Nick Matthew (ENG) bt Daryl Selby (ENG) 12-10, 11-7, 11-8 (65m)
[5] Gregory Gaultier (FRA) bt Omar Mosaad (EGY) 11-6, 4-11, 11-4, 11-6 (68m)
[6] Peter Barker (ENG) bt Cameron Pilley (AUS) 11-8, 11-7, 11-4 (47m)
[3] James Willstrop (ENG) bt Olli Tuominen (FIN) 11-3, 11-8, 11-6 (30m)
[4] Amr Shabana (EGY) bt Hisham Mohamed Ashour (EGY) 11-5, 11-7, 12-10 (31m)
Mohd Azlan Iskandar (MAS) bt [7] Mohamed El Shorbagy (EGY) 6-11, 11-6, 14-12, 11-7 (56m)
Stewart Boswell (AUS) bt Tom Richards (ENG) 11-4, 11-9, 11-0 (42m)
[2] Karim Darwish (EGY) bt [Q] Tarek Momen (EGY) 11-3, 11-2, 5-11, 11-7 (41m)

Quarter-final line-up:
[1] Nick Matthew (ENG) v [5] Gregory Gaultier (FRA)
[3] James Willstrop (ENG) v [6] Peter Barker (ENG)
[4] Amr Shabana (EGY) v Mohd Azlan Iskandar (MAS)
[2] Karim Darwish (EGY) v Stewart Boswell (AUS)

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