Paul Kinghorn, Kristian Wilkinson and Mark Dring took two wickets apiece as the visitors posted 122-8, mainly thanks to a superb 73 from Michael Artley.
A 95-run third-wicket stand from Ryan Wharton (63no) and skipper Sam Triffitt (50no) then saw third-placed Heslerton home.
Leaders Folkton & Flixton 2nds earned a seven-wicket success at rivals Wykeham.
Jack Stephenson’s 3-9 and 3-19 from Chris Mann pegged Wykeham back to 134-9, Mike Dugdale (36) and Joe Bradshaw (29) the only batsmen to shine.
Opener Jack Walmsley’s excellent 71no, allied to James Clark’s 34 saw Flixton home with plenty to spare.
Great Habton’s fine all-round effort helped them to a six-wicket home win against promotion rivals Thornton Dale.
Stuart Whatmore’s 4-19 and a three-wicket haul from Jim Boyes dismissed Dale for 113.
Doug Bentley (35no) and Dan Hardy (35) steered Habton safely to the win.
Jack Pickard’s stunning knock of 114 helped Sherburn to a 119-run triumph at Forge Valley.
Pickard crashed 18 fours and two sixes in his 93-ball stay, helping the visitors recover from 122-6, mainly thanks to a seventh-wicket stand of 69 with Daley Wharton (31), to post 219-8. Luke Calvert took 3-49 for Valley.
Only Sean Pinder (39) and Alex Glass (25) showed any fight for the hosts in reply, as they slipped to 100 all out, Jamie Thomson bagging 4-21.
Cayton 2nds claimed a crucial six-wicket victory at home to eight-man Settrington.
Charlie Meatheringham, Jake Seastron and Chris Pearson took two wickets each as Setty were all out for 93, skipper Ben Corner top-scoring with 27.
Corner and Tris Midgley took two wickets each to keep the visitors in the game, but Richard Seastron hit 31 and his son Jake Seastron added 35 to cap a fine day for the skipper.
Staithes remain top of the Premier Division after a straightforward eight-wicket success at 10-man strugglers Staxton.
Chris Morrison’s superb 4-14 in 10 overs saw Staxton all out for 97, only a defiant 22no from Mick Witty, with Joe Stearman’s 19, lifting the hosts with a last-wicket stand of 49.
Morrison then struck 39 and Gary Sivills 35no as Staithes eased to the win in 18.2 overs.
Josh Dawson was the all-round star as second-placed Filey secured a five-wicket victory at Ebberston.
Dawson snapped up 4-36 and Phil Dickens 3-23 as the hosts were skittled for 95, despite the best efforts of openers Jon Mason (24) and Jake Finnegan (28).
Frankie Beal’s 3-28 gave Filey a few worries and it took an unbeaten 36 from skipper David Brannan and an explosive 33 in just 10 balls, including four sixes and two fours, by Dawson to seal the win for the away side.
Scalby stayed in touch with the top two, and with a game in hand, with a six-wicket win at Brompton.
An opening stand of 64 between Robin Siddle (29) and Tom Bruce (35) gave Brompton a solid foundation, then Tom Fletcher-Varey hit 32 and Toby McGill 24 as they posted 163-7, James Deaves bagging 3-34.
Skipper Chris Malthouse then hit 34, Jon Barton 35 and Ben Luntley 40no to seal the win with 7.5 overs to spare.
Andy Raw and Chris Knight were the all-round stars in Mulgrave’s 21-run triumph at home to Bridlington 2nds.
Knight shone with 60 and Raw 59no as Mulgrave posted 191-8, Carl Parkin taking 3-56.
Raw then took 3-27 and Knight 2-14 as Bridlington were pegged back to 170-9, openers Steve Pockley and Greg Miller top-scoring with 48 and 29 respectively.
Cloughton climbed off the foot of the table with a 58-run home success against Cayton.