Sheffield RUFC kept pole position in North One East but struggled for a 12-10 win at lowly Bradford and Bingley.
They had tries by flanker David Bradford and winger Ali Womack.
With second-placed Ilkley picking up a bonus for scoring five tries in a 31-7 win at Alnwick, Sheffield’s lead is now down to just two league points but they have a game in hand ahead of next Saturday’s rearranged clash with Wheatley Hills at Abbeydale.
Sheffield Tigers’ National Three match against Wirral was postponed after the visitors to refused to play on the Dore Moor pitch, despite two referees having inspected it and passed it fit to play.
Dinnington moved up to third place when they trounced visitors Percy Park 44-13 with a six-try performance at Lodge Lane.
Will Marshall crashed over for two early tries and Chris Williams added another. Jonny West converted the first, but then handed over kicking duties to Williams who converted a try by centre Tyle Stimpson. Williams then landed two penalties before converting whe Steve Thompson touched down after a break started in their own 22 by flanker Jalan Farras.
At the death, Stimpson kicked through and the ball was picked up by winger Rob Leivars, who went in between the posts to give Williams another simple conversion.
In Yorkshire One, Wath on Dearne suffered their second defeat of the season by Bridlington, going down 36-10 at Moor Road. Brad Taylor scored a try in either half for Wath, but both were well out on the wing and full-back Sam Jones missed the conversions.
In Yorkshire Two, Sheffield Medicals scored four tries as they beat Barnsley 30-20 at home.
Stocksbridge, hammered 62-7 at Thorne last October, turned the tables with a 29-0 victory over higher placed Thornensians in Yorkshire Three at Bolsterstone. Scott Bowskill converted first-half tries by Liam O’Leary, Sam Whitaker and Peter Newton, and Stocksbridge collected a four-try bonus when Andrew Beal touched down.