Southern Vipers stayed top of the Rachael Heyhoe Flint Trophy table with victory over Thunder despite the best efforts of England’s Kate Cross.
She hit 57 off 86 balls and took 2-34, but Thunder only made 110 all out and Vipers won by three wickets on 112-7.
Hollie Armitage made an unbeaten 68 as Northern Diamonds stayed second, beating Western Storm by seven wickets.
Elsewhere, South East Stars defeated Lightning in a high-scoring game and Central Sparks beat winless Sunrisers.
With two rounds of games remaining, Vipers head the table by one point from Northern Diamonds, with Central Sparks two behind in third.
The group winners will qualify for the final at Northampton on 25 September, with the teams finishing second and third playing an eliminator match three days earlier.
Vipers are the defending champions in the 50-over format and even more eager to repeat last summer’s success after missing out on the Charlotte Edwards Cup final last weekend, when South East Stars lifted the T20 trophy.
Their fourth win in five games appeared straightforward after Thunder’s innings only lasted 32.5 overs at Sale CC as Tara Norris claimed 4-14 and only one other batter apart from Cross – who hit a six and five fours – reached double figures.
Cross, though, had both Georgias – Adams and England team-mate Elwiss – caught behind as Vipers struggled to 68-5 despite 41 by Ella McCaughan, before Emily Windsor’s 26 not out guided them home with more than 16 overs of their innings remaining.
Northern Diamonds had even more to spare as they chased down a target of 184 at the Riverside in just 31.1 overs.
Western Storm, with only one win from their four previous games, reached 109-2 in the 19th over but then lost four wickets for three runs. They were eventually all out for 183 despite skipper Sophie Luff’s 65 off 77 balls, as left-arm spinner Linsey Smith returned figures of 5-34.
England’s Lauren Winfield-Hill was lbw to Georgia Hennessy for 16 at the start of the reply before Armitage and Sterre Kalis (32) added 59 for the second wicket.
Armitage struck seven fours in her 69-ball innings and an unbroken partnership of 54 in nine overs with Bess Heath (32 not out) finished the job.
South East Stars piled up 293-9 at Beckenham with Bryony Smith and Alice Capsey, two of the stars of their Charlotte Edwards Cup triumph, again in the runs against Lightning.
Smith hit 12 fours in her 84 off 73 balls, and Capsey made 78 from 73 before she was run out, while Kalea Moore weighed in with 39 before she gave a return catch to Kathryn Bryce (2-50).
Lightning made a decent attempt at the run chase, achieving their highest total of the competition so far, as Bryce’s 87 led them to 265 before they were finally all out with four balls of their innings left.
The match at Northwood was reduced to 42 overs because of rain, and opener Cordelia Griffith’s 69 off 95 balls helped Sunrisers to 204-7 against Central Sparks.
Marie Kelly (58 off 63 balls) and Evelyn Jones (31) launched the reply with an opening stand of 84, and Gwen Davies made exactly 50 from 59 as they reached 208-4 in the 38th over to win by six wickets via the DLS method.
Remaining group fixtures
12 September: Northern Diamonds v Thunder (Riverside), Central Sparks v South East Stars (Worcester), Western Storm v Lightning (Bristol), Sunrisers v Southern Vipers (Chelmsford)
18 September: Lightning v Central Sparks (TBC), South East Stars v Thunder (Beckenham), Western Storm v Sunrisers (Bristol), Southern Vipers v Northern Diamonds (Southampton)