Mueller is a hugely talented prospect, but the Englishman imposed his own style on the game to win 11-9, 11-6, 11-6 in 38 minutes.

"Nic is already a very dangerous and although it's nice to get off court quickly in the early rounds I am just happy with the win," said Willstrop, the world No2 from Leeds. "He is already giving top ten players a difficult time, so winning quickly against him was simply a bonus."

Willstrop now meets French veteran Thierry Lincou in the second round. Lincou played the fall guy as he met wild card Patrick Chifunda, the club-based Zambian coach who attracted a full-house gallery to the Westwood Club.

The crowd cheered their local hero to the rafters as he dived around the court and every winner earned a raucous standing ovation.

Lincou sportingly engineered an entertaining straight games victory, allowing Chifunda to go tantalisingly close in the third game before he clinched victory 11-3, 11-3, 11-8.

Seeds Gregory Gaultier, Amr Shabana and Mohd Azlan Iskandar all marched forward with straight games victories - but there was a major shock when world No11 Hisham Mohamed Ashour collapsed to England's Adrian Grant.

The left-handed Londoner played fast, direct squash and moved superbly to work his Egyptian opponent out of position to win 11-7, 11-6, 11-3 in 30 minutes.

Grant now meets fellow left-hander Shabana and he admitted: "My target for this year is to get back up to the world top ten. My body is still holding up well and I felt good on court tonight."

Cairo qualifier Karim Abdel Gawad made up for the Egyptian disappointment by claiming an unexpected second round place after upsetting Australia's Ryan Cuskelly 11-8, 11-9, 11-9.

Gawad, the 20-year-old world No42, now lines up against eighth seed Iskandar, ranked 32 places higher.

RESULTS: PSA World Series Davenport North American Open, Richmond, Virginia, USA

1st round (top half of draw):
[1] James Willstrop (ENG) bt Nicolas Mueller (SUI) 11-9, 11-6, 11-6 (38m)
Thierry Lincou (FRA) bt Patrick Chifunda (ZAM) 11-3, 11-3, 11-8 (30m)
Adrian Grant (ENG) bt Hisham Mohamed Ashour (EGY) 11-7, 11-6, 11-3 (30m)
[6] Amr Shabana (EGY) bt [Q] Siddharth Suchde (IND) 11-3, 11-5, 11-5 (32m)
[8] Mohd Azlan Iskandar (MAS) bt [Q] Campbell Grayson (NZL) 11-6, 11-8, 11-5 (45m)
[Q] Karim Abdel Gawad (EGY) bt Ryan Cuskelly (AUS) 11-8, 11-9, 11-9 (55m)
Shahier Razik (CAN) bt Saurav Ghosal (IND) 13-11, 6-11, 11-9, 11-6 (72m)
[3] Gregory Gaultier (FRA) bt [Q] Olivier Pett (ENG) 11-5, 11-6, 11-7 (32m)

Remaining 1st round matches:
[4] Ramy Ashour (EGY) v [Q] Matthew Karwalski (AUS)
Cameron Pilley (AUS) v [Q] Shawn Delierre (CAN)
Alan Clyne (SCO) v [Q] Zac Alexander (AUS)
[5] Karim Darwish (EGY) v [Q] Mathieu Castagnet (FRA)
[7] Laurens Jan Anjema (NED) v Alister Walker (BOT)
Simon Rosner (GER) v Chris Ryder (ENG)
Olli Tuominen (FIN) v Julian Illingworth (USA)
[2] Nick Matthew (ENG) v Miguel Angel Rodriguez (COL)

Event website: www.naosquash.com
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