Danni Wyatt brought Southern Vipers home in a 10-over chase against Central Sparks as they began their defence of the Rachael-Heyhoe Flint Trophy with a seven-wicket victory in Birmingham.
After Sparks posted 163-7 in 36 overs, reduced by rain, further delays left Vipers with 70 to chase in 10 and Wyatt made 36 from 24 balls to win it.
Elsewhere, Bryony Smith scored 66 and took three wickets to lead South East Stars to victory over Sunrisers.
And Western Storm won at Lightning.
Vipers have won both editions of the competition since its formation and it took a quick dash from Wyatt to get their new campaign off to a winning start.
Eve Jones' 39 was the only significant contribution as Sparks were held to a modest total after being sent in.
Vipers were left needing five from the final over before Georgia Elwiss cleared the ropes to seal victory with two balls to spare.
At Beckenham, Smith's 68-ball innings helped her side post 281-8 after winning the toss, with Alice Capsey making an unbeaten 64 and Kira Chathli 61.
Grace Scrivens led the reply with 74 but she was Smith's second victim as the Stars captain claimed 3-37 and Sunrisers were bowled out for 201.
And at Loughborough, captain Sophie Luff made 48 and Fran Wilson 43 as Storm compiled 260-9 after losing the toss.
Danielle Gibson then took two wickets and effected a run-out as Lightning reached 166-9 before rain curtailed the chase and Storm won by 75 runs on Duckworth-Lewis-Stern method.
The game was notable for umpires Naeem Ashraf and Jasmine Naeem becoming the first husband and wife to officiate in a professional fixture in England together.
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