English qualifier Olivier Pett produced a stunning upset on the opening day of action in the Berkshire Open in the USA when he defeated Malaysia's Mohd Nafiizwan Adnan in straight games to reach the quarter-finals of the PSA World Tour International 35 event in its eighth year at Williams College in Williamstown, Massachusetts.

"Pett survived two rounds of qualifying and then upset world-ranked #34 Nafiizwan Adnan, whose beautiful movement but emotionally passive play allowed a more determined Pett to out-work and out-position Adnan in a lengthy three-gamer," said tournament organiser Zafi Levy, the college's Head Squash Coach.

Following his 11-7, 11-9, 12-10 victory in 50 minutes, the 23-year-old world No68 from Sussex (pictured with Adnan) goes on to meet top seed Alister Walker, the world No18 from Botswana.

US-based Walker struggled more than expected in downing Chris Simpson, the world No46 from England 13-11, 11-9, 6-11, 11-5 in 74 minutes. Simpson had two game balls in the first, stayed even in the second then won the third before finally running out of gas in the fourth.

Borja Golan, the third seed from Spain, was considerably more efficient in despatching English qualifier Charles Sharpes 11-5, 11-1, 11-4 in 27 minutes.

The most entertaining - and longest - match of the evening paired Canadian Shawn Delierre against Australian qualifier Scott Arnold.

"As usual, when Shawn plays, there were lots of lets and lots of litigating," explained Levy. "Shawn's opponents tend to take his on-court behaviour personally, which is understandable, but the truth is that he just happens to bring his own personality on court just like everyone else.

"He has a great racquet and wonderful anticipation, and if you leave loose balls for him to work with, he is remarkably efficient in outmanoeuvring his opponents, as he did tonight."

Delierre beat Arnold 11-6, 11-6, 11-13, 11-9 in 82 minutes and next faces Golan.

1st round (top half of draw):
[1] Alister Walker (BOT) bt Chris Simpson (ENG) 13-11, 11-9, 6-11, 11-5 (74m)
[Q] Olivier Pett (ENG) bt Mohd Nafiizwan Adnan (MAS) 11-7, 11-9, 12-10 (50m)
Shawn Delierre (CAN) bt [Q] Scott Arnold (AUS) 11-6, 11-6, 11-13, 11-9 (82m)
[3] Borja Golan (ESP) bt [Q] Charles Sharpes (ENG) 11-5, 11-1, 11-4 (27m)

Outstanding 1st round matches:
[4] Stephen Coppinger (RSA) v Julian Illingworth (USA)
Arturo Salazar (MEX) v Yasir Butt (PAK)
Miguel Angel Rodriguez (COL) v [Q] Christopher Gordon (USA)
[2] Tom Richards (ENG) v Siddharth Suchde (IND)

Qualifying finals:
Olivier Pett (ENG) bt Peter Creed (WAL) 11-9, 11-9, 11-1 (39m)
Christopher Gordon (USA) bt Jaymie Haycocks (ENG) 11-9, 11-4, 11-3 (44m)
Scott Arnold (AUS) bt Eddie Charlton (ENG) 11-6, 11-5, 5-11, 11-2 (55m)
Charles Sharpes (ENG) bt Ben Coleman (ENG) 11-7, 11-6, 8-11, 11-7 (66m)

1st qualifying round:
Olivier Pett (ENG) bt Adrian Dudzicki (CAN) 11-9, 11-4, 10-12, 11-2 (39m)
Peter Creed (WAL) bt Tyler Hamilton (CAN) 11-5, 11-8, 11-9 (44m)
Jaymie Haycocks (ENG) bt Fred Reid (CAN) 11-6, 11-9, 11-4 (24m)
Christopher Gordon (USA) bt Clinton Leeuw (RSA) 11-4, 16-14, 2-11, 11-3 (64m)
Eddie Charlton (ENG) bt Josh Cardwell (AUS) 12-10, 11-4, 11-2 (41m)
Scott Arnold (AUS) bt Dane Sharp (CAN) 11-2, 11-5, 3-11, 11-9 (38m)
Ben Coleman (ENG) bt Wade Johnstone (AUS) 11-8, 11-8, 11-7 (51m)
Charles Sharpes (ENG) bt Thomas Brinkman (CAN) 12-10, 11-13, 11-2, 11-7 (44m)