The leaders face rock-bottom Heaton in their final fixture next week and the Bradford club have won only one match all season.
This week Barnsley battled to a 16-8 home triumph against Abbeydale, with Ashley Davies, Tom Bamford and Oli Harris sealing the five bonus points with victories over Matthew Broadberry (3-0), Adam Turner (3-2) and Oli Turner (3-0).
Adam Murrills and Nick Wall junior ensured the match went the full distance, though, by overcoming South African Shaun le Roux 3-2 and Millie Tomlinson 3-0.
Meanwhile, Hallamshire registered a more comfortable 18-8 success at Hull and East Riding, where Mark and Chris Fuller, Alex Cutts and Jack Alcock defeated Harry Falconer 3-2, Fi Moverley 3-0, Glyn Saunders 3-1 and Yusef Forster 3-2.
Paul Norton notched the home team’s consolation victory at No 5, by a 3-1 margin against Dan Lawrence.
Barnsley and Hallamshire are now well clear of the chasing pack, as defending champions Dunnington slumped to an 18-8 loss at Queens to fall 52 points behind Hallamshire in third place.
James Earles, Connor Sheen and Sarah Campion guided the Halifax outfit home by beating Gareth Lumsdon 3-0, Ed Shannon 3-0 and Matthew Stephenson 3-2.
Danny Hockborn and Nathan Hill kept the York team’s hopes alive with 3-2 wins over Matt Sidaway and Tom Whiteley.
The night’s other match ended in another heavy defeat for Heaton. They crashed 20-3 at Chapel Allerton, who fielded former world No 2 Jenny Duncalf at No 3.
The current world No 16 was one of three straight-games winners, defeating Mathew Powell, while Eddie Charlton and Dom Hamilton overpowered Stuart Macgregor and Phil Bowker.
The other two rubbers ended in a 3-2 success for former world No 3 Simon Parke over Isaac Rawcliffe and a 3-1 victory for Adam Wellstead over Darren King.
The Pontefract derby was postponed until April 6.