Egyptian Tarek Momen made an impressive debut today in the Cathay Pacific Sun Hung Kai Financial Hong Kong Open when he beat Swiss opponent Nicolas Mueller in a high-paced battle to become the only qualifier to make the last 16 round of the seventh PSA World Series squash event of the year.

The 23-year-old from Cairo - who has never before played in the popular PSA World Tour event celebrating its 25th staging this year - is one of six Egyptians to secure a place in Tuesday's second round.

In fact, since the Hong Kong Open draw was made, Momen has leapt to 19 in the world rankings - now three places ahead of the Zurich-born 22-year-old whom he was facing on the Tour for the first time.

Mueller prevailed in a tight and prolonged opening game - but Momen struck back to prove his new ranking superiority over his unseeded opponent to win 15-17, 11-4, 11-8, 11-7 in 48 minutes.

The rising star of Egyptian squash will now face compatriot Karim Darwish. The second seed, ranked six in the world, took just 27 minutes to overcome Malaysian qualifier Ivan Yuen - the only player in the draw ranked outside the top 100 - 11-5, 11-5, 11-4.

Another all-Egyptian second clash will see four-time champion Amr Shabana take on Cairo colleague Hisham Mohamed Ashour. Shabana, the distinguished former world number one who is making his 14th successive appearance in the championship since 1996, was fully tested by event newcomer Mohd Nafiizwan Adnan before beating the Malaysian qualifier 11-9, 11-9, 3-11, 11-1.

Ashour, older brother of the injured defending champion Ramy Ashour, battled for 47 minutes to see off experienced Malaysian Ong Beng Hee, a quarter-finalist in 2001 and 2002, 11-6, 11-7, 7-11, 11-9 in 47 minutes.

In the other upset of the day, Stewart Boswell doubled the Australian interest in the last 16 round when he defeated eighth seed Thierry Lincou in straight games.

Frenchman Lincou, always a favourite with the Hong Kong crowd since his title triumph in 2004, looked flat after his recent exploits in Macau, and although he briefly threatened a comeback in the third Boswell closed out the match 11-3, 11-9, 11-5 in 45 minutes.

And England's Tom Richards was close to becoming another unexpected first round casualty when he twice faced match-ball against him from French qualifier Mathieu Castagnet.

After the first four games were shared, the Englishman led the way in the decider, but pure determination saw Castagnet come back and earn two match balls at 10-8.

A despairing dive into the back corner couldn't stop Richards levelling and the Englishman completed a run of four points to win 8-11, 11-5, 11-8, 2-11, 12-10 in 77 minutes.

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

1st round (lower half of draw):
[4] Amr Shabana (EGY) bt [Q] Mohd Nafiizwan Adnan (MAS) 11-9, 11-9, 3-11, 11-1 (40m)
Hisham Mohamed Ashour (EGY) bt Ong Beng Hee (MAS) 11-6, 11-7, 7-11, 11-9 (47m)
Mohd Azlan Iskandar (MAS) bt [Q] Gregoire Marche (FRA) 11-4, 11-7, 11-1 (33m)
[7] Mohamed El Shorbagy (EGY) bt [Q] Alan Clyne (SCO) 11-8, 11-8, 11-6 (34m)
Stewart Boswell (AUS) bt [8] Thierry Lincou (FRA) 11-3, 11-9, 11-5 (45m)
Tom Richards (ENG) bt [Q] Mathieu Castagnet (FRA) 8-11, 11-5, 11-8, 2-11, 12-10 (77m)
[Q] Tarek Momen (EGY) bt Nicolas Mueller (SUI) 15-17, 11-4, 11-8, 11-7 (48m)
[2] Karim Darwish (EGY) bt [Q] Ivan Yuen (MAS) 11-5, 11-5, 11-4 (27m)

2nd round line-up:
[1] Nick Matthew (ENG) v Daryl Selby (ENG)
[5] Gregory Gaultier (FRA) v Omar Mosaad (EGY)
[6] Peter Barker (ENG) v Cameron Pilley (AUS)
[3] James Willstrop (ENG) v Olli Tuominen (FIN)
[4] Amr Shabana (EGY) v Hisham Mohamed Ashour (EGY)
[7] Mohamed El Shorbagy (EGY) v Mohd Azlan Iskandar (MAS)
Stewart Boswell (AUS) v Tom Richards (ENG)
[2] Karim Darwish (EGY) v [Q] Tarek Momen (EGY)

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