New British National champions Nick Matthew and Alison Waters led their teams to victory in tonight's eighth round of the Premier Squash League (PSL) – with Waters helping Croydon club Surrey Health & Racquets consolidate their leadership of Group B in the countdown to the end-of-season play-offs in the world's most prestigious squash league.

Londoner Waters, winner of the women's national title on Sunday in Manchester for the second time, beat Dominique Lloyd-Walter 13-11, 11-6, 11-7 as Surrey Health & Racquets forged a 3/2 away win against Covers Chichester. The south coast side put the pressure on former champions Surrey Health, with Olivier Pett and Robbie Temple gaining two notable wins – 21-year-old Pett, ranked 298 in the world, twice coming from behind to beat experienced Ben Ford 8-11, 11-8, 7-11, 11-9, 13-11, and 23-year-old Londoner Robbie Temple fighting back from two games down to topple the visitors' in-form Scottish international Alan Clyne 2-11, 8-11, 11-8, 11-7, 11-8.

But England international Peter Barker clinched the win for Surrey Health after beating Malaysian international Mohd Azlan Iskandar 11-4, 10-12, 11-9, 11-7 to maintain his club's supremacy in Group B from the beginning of this year.

But only one point behind the group leaders are TWP St George's Hill, who stormed to a maximum points 5/0 away win at county rivals Surrey Storm Guildford.  Again it was a National Championships star who played a decisive role – Daryl Selby, who reached the men's semi-finals against the odds for the first time, beating Guildford's South African international Jesse Engelbrecht in four games to ensure a whitewash for the visitors.

Exeter Diamonds strengthened their grip on third place in the Group B points table with a 3/2 win at Probuild Bristol.  New Zealand's Jaclyn Hawkes, together with Joey Barrington and local star James Snell, gave the west country visitors an unassailable lead – but Bristol-based university student Mohamed El Shorbagy, the world No14 from Egypt,  and England's world No10 Adrian Grant reduced the deficit with five-game wins over Exeter's Jonathan Kemp and Australian Stewart Boswell, respectively.

Nick Matthew, who successfully defended his men's national title at the National Squash Centre at the weekend, was able to reproduce the same form for Benz-Bavarian Duffield – and the Derbyshire club became the only home winners on the day, beating reigning champions LEBC Group Chapel Allerton 3/2 in Group A.  But whilst Matthew beat French rival Thierry Lincou, the former world No1, 9-11, 11-6, 11-8, 11-6, it was his South African team-mate Stephen Coppinger who clinched victory for former champions Duffield by beating England's higher-ranked Alister Walker 11-4, 6-11, 11-9, 11-9.

But former champions MB Nottingham scored the biggest win in the group – and extended their lead in the Group A points table – with a 4/1 victory at Newport, the league's Welsh newcomers.  A succession of wins by Emma Beddoes, Lewis Walters, Arthur Gaskin and team stalwart Simon Parke, gave the East Midlands a decisive lead – but Australian Aaron Frankcomb provided a consolation win for the hosts when he beat Nottingham top string John Rooney 11-9, 1-11, 7-11, 11-9, 11-3.

Pontefract entertained Esporta Oxford and provided two popular wins when top string James Willstrop made up for a disappointing Nationals' final appearance with a brilliant straight games victory over Australian international Cameron Pilley, and former club number one Lee Beachillshowed that retirement hasn't blunted his attack by despatching the visitors Scott Handley in three games.

But it was ultimately Oxford's night as 11-time Irish champion Madeline Perry battled back from two games down to beat the home team's Dutch star Vanessa Atkinson after a tie-break in the decider, and Jaymie Haycocks and Chris Ryder also scored notable triumphs.  The 3/2 win moves Esporta Oxford up to second position in the Group tables, just eight points behind leaders Nottingham