Southern Vipers left Chesterfield victorious courtesy of a Georgia Elwiss hundred and a half-century from Abi Norgrove, handing The Blaze just their second defeat in 15 matches.
Coming together with the score on 124/4, the pair batted for over two hours to guide the top of the table side to their sixth win in eight matches, despite a late wobble with Kathryn Bryce taking two wickets in an over.
Earlier in the day, The Blaze had posted 278 all out, Kathryn Bryce hitting another half-century and Heather Graham blasting a quick fire 79.
Under sunny skies at Queen’s Park Kirstie Gordon won the toss and elected to bat first, Lucy Higham replacing Michaela Kirk in the only change from the side that were victorious over South East Stars on Sunday.
Teresa Graves, on the occasion of her 50th cap, was run out at the end of the sixth over, after adding 28 for the opening wicket Sarah Bryce.
That early breakthrough for the visitors brought Kathryn Bryce to the middle, the Scottish all-rounder being named the PCA Player Of Month for June before the start of play.
The Bryce sisters, like they have done on numerous occasions already in 2024, made serene progress, adding 71 inside 12 overs before Sarah fell for 48, caught at point off Ava Lee.
Kathryn found ample support in the shape of in-form Marie Kelly (30) as she cantered to her sixth half-century in 14 matches for The Blaze this summer, departing having made 65 from 72 deliveries.
That laid the platform for some late-order fireworks, an invitation that Heather Graham duly answered.
The Australian international added a first half-century for The Blaze, to go with her maiden five-wicket haul in the victory over the Stars as Gordon’s side made their second successive score of 250+ in the 50-over competition.
Finding the rope on 12 occasions, and clearing it once, Graham’s 59-ball 78, her 14th fifty in List A cricket lifted The Blaze to 278 all out.
In response, Grace Ballinger provided the perfect start, swinging a ball into the pads of Charlie Knott, the Australian sent on her way for a run-a-ball 8.
Despite the early breakthrough, runs were flowing quickly for the visitors, Ella McCaughan (26) and Georgia Adams putting on 65 inside just over 11 overs for the second wicket.
After McCaughan departed, the experienced duo of Adams and Georgia Elwiss picked up the mantle, before a moment of brilliance in the field changed the momentum once more.
Adams (47), looking to come back for a tight second, was stranded short after a Lucy Higham direct hit from the boundary, before Cassidy McCarthy removed Emily Windsor four balls later.
That would be the last of the breakthroughs for the hosts for a while though as a blend of experience and youth combined to take the visitors to the brink of victory in some style.
Former England player Elwiss, who represented her country over 50 times, and 18-year-old Abi Norgrove put on a masterclass in chasing, their 136-run fifth-wicket stand pushing the Vipers within touching distance of their target.
Kathryn Bryce removed Norgrove (64) and Alice Monaghan (1) in the 48th over, but Elwiss’ first maximum took the Vipers to victory and the England batter to her century with five balls remaining.
The Blaze head to Cheltenham to face Western Storm next week, before rounding out the block of 50-over fixtures with the visit of Northern Diamonds to Lindum Sports Ground, a week on Sunday.