While Barnsley were battling to a 16-10 success at Queens, Hallamshire were coasting to an 18-7 home victory over Chapel Allerton to move to within 11 points of the leaders on 230 points with four rounds left.
The scene is now set for a probable title decider on Wednesday between the two clubs at Barnsley.
Hallamshire claimed four of the five rubbers against Chapel Allerton, with Mark and Chris Fuller, Neil Guirey and Dan Lawrence victorious against Eddie Charlton (3-2), Simon Parke (3-0), Niall McKinnon (3-1) and James Butterworth (3-1).
Only Jack Alcock – at No 3 – was beaten, but he still picked up a point in his 3-1 loss to Dom Hamilton.
In contrast, Barnsley generally had to really fight for their 16 points, with only Oli Harris scoring a comfortable win – in straight games against Danny Bray.
The visitors’ two other victories – by Tom Bamford and Millie Tomlinson against Connor Sheen and Sarah Campion – were both by 3-2 margins, which was also the score in Ashley Davies’ defeat by Queens’ Matt Sidaway. At first string, meanwhile, Queens’ James Earles routed Shaun le Roux 3-0.
Dunnington’s 15-9 home triumph against Abbeydale was just as tightly contested as they held on to third place – 49 points behind Hallamshire – thanks to wins by Danny Hockborn, Matt Marshall and Matthew Stephenson over Matthew Broadberry (3-1), Nick Wall Jnr (3-2) and Charlie Wall (3-0).
Adam Murrills and Oli Turner ensured the match went the distance by beating Gareth Lumsdon 3-0 and Ed Shannon 3-1.
At the other end of the table, Heaton and Pontefract 2nds fell further adrift of the rest of the division after their respective 15-8 and 18-10 defeats by Pontefract 1sts and Hull and East Riding.
Pontefract 2nds are now 51 points behind eighth-placed Hull and ER, who eased home on the back of victories from Andy Cockerill, Glyn Saunders, Yusef Forster and Paul Norton over George Wileman (3-2), Elliot Ridge (3-1), Matt Godson (3-2) and Ben Hodgetts (3-2).
Hull and ER’S solitary defeat came at first string, where Harry Falconer went down 3/1 to Patrick Rooney.
Pontefract 2nds in turn are 31 points ahead of bottom side Heaton, after the Bradford team lost three of their rubbers at Pontefract 1sts, Julian Tomlinson, Mathew Powell and Phil Bowker succumbing to Taminder Gata Aura (3-1), Sam Wileman (3-0) and Adam Taylor (3-1).
However, Heaton made Pontefract work for their winning bonus points, as Jan van den Herrewegen overcame Alex Hodgetts 3-0 and Stuart Macgregor beat Lewis Doughty 3-1.