TWP St George's Hill's unbeaten run in this season's Premier Squash League (PSL) came to a dramatic end when the Group B leaders slumped 3/2 to Team Chichester in the eighth round of the of the world's most prestigious squash league.

Meanwhile defending champions Surrey Health & Racquets continued their strong form in the group by thumping UWE Bristol 5/0 – earning their fourth successive PSL win and dramatically reducing the gap behind St George's Hill in the tables.  Third-placed Exeter Diamonds weakened their bid for a place in the end-of-season play-offs by going down 3/2 at home to PSL newcomers IGT Winchester.

 ormer champions LEBC Group Chapel Allerton strengthened their lead in the Group A tables with a 4/1 away win at MB Nottingham – while England's world number one Nick Matthew played a decisive role in Benz-Bavarian Duffield gaining a 3/2 away win over CLFS Esporta Oxford to improve their chances of a play-off place.

It was a rueful St George's Hill manager Danny Lee who commented "the wrong Lee won" after his son Joe Lee lost to Chichester's late replacement Alex Gough, while Chichester's Max Lee recorded a marathon victory over British National Champion Daryl Selby.

Guyana's Nicolette Fernandes started the Chichester run by upsetting the home side's Dominique Lloyd-Walter in five games – while the now-retired Alex Gough, a former world No5, produced one of the shocks of the season by despatching world No63 Joe Lee 13-11, 11-5, 11-7 in just 36 minutes.

The home crowd sensed that normal service would be resumed as middle order stalwarts Nafiizwan Adnan and Mark Krajcsak levelled the tie – and hopes were high that Selby would rediscover the form that saw him lift the British National title against expectations less than a month ago.

And the world No10 from Essex led 2/1 against Max Lee before the Hong Kong 22-year-old – ranked 52 places lower in the world – pulled off one of the best wins of his career to beat Selby 13-11, 11-13, 8-11, 12-10, 11-5 in 77 minutes.

Surrey Health & Racquets dropped just two games in their commanding victory over former runners-up UWE Bristol.  England international Alison Waters laid down a marker for the hosts with an 11-4, 11-8, 11-7 win over Bristol's Sarah-Jane Perry – and Ben Ford, captain Tim Garner, Adrian Waller duly followed Waters' winning example before top-ranked Scot Alan Clyne ensured maximum points by beating rising French star Lucas Serme 10-12, 11-5, 11-2, 11-7.

It was French number one Gregory Gaultier, making only his second appearance for the club, who led IGT Winchester to their 3/2 away win over Exeter Diamonds.  With the tie poised at two-all, world No6 Gaultier recovered from two games down to beat Exeter's Stewart Boswell 10-12, 6-11, 11-8, 11-6, 11-6 – inflicting the first defeat of the season on the Australian international.

It was a similar story in Oxford where Derbyshire club Benz-Bavarian Duffield, the three times champions eager to make the final for the first time in two years, were level at two matches apiece against CLFS Esporta Oxford.  The decider saw the world's top player Nick Matthew take on the top Spaniard Borja Golan.  World champion Matthew took the opening two games, but Golan battled back to draw level.

Disappointment for the hosts was matched be elation for the visitors when Matthew recovered the advantage to win 11-5, 15-13, 11-13, 11-7.  The win strengthens Duffield's position in third place in the Group A tables, just three points adrift of Oxford – but with a tie in hand.

LEBC Group Chapel Allerton began their victory bid at MB Nottingham a match down after local star Emma Beddoes beat the Yorkshire club's Carrie Ramsey 11-3, 11-5, 11-3.

But stirring wins by the visitors' Anthony Graham, Shaun le Roux, Laurence Delasaux and Chris Simpson gave Chapel Allerton the 4/1 win which extends their lead at the top of the Group A tables to 23 points ahead of Esporta Oxford.