London Spirit 122 for 2 (Mooney 61*, Gibson 34) beat Welsh Fire 119 for 9 (Bryce 33, Davies 3-25) by eight wickets
Freya Davies and Amelia Kerr starred with the ball as London Spirit broke their duck at the fourth attempt in this year's Hundred with an emphatic eight-wicket victory over still-winless Welsh Fire.
England quick Davies struck twice in two balls on her way to figures of 3 for 25, while New Zealand legspinner Kerr took the crucial wickets of Sarah Bryce and Nicola Carey in a miserly spell of 2 for 14 to restrict Fire to a below-par 119.
Australian legend Beth Mooney made light of the chase, finishing unbeaten on 61 after sharing an opening stand of 66 with pinch-hitter Danielle Gibson as Spirit got home with 14 balls to spare.
Having failed to chase down a score in their three previous matches Fire understandably chose to bat on winning the toss, but their innings followed a familiar pattern.
Bryce, promoted to fill the shoes of Hayley Matthews, who had departed to the Caribbean Premier League, gave early impetus, latching onto some short pitch bowling from Spirit to score boundaries either side of the wicket and despatching a full toss from the otherwise impressive Kerr over the ropes for the only six off the innings.
Skipper Tammy Beaumont too flourished briefly in an opening stand of 46 before missing a straight one from Davies which flattened her middle stump. Davies then made it two in two with a peach of an inswinger which castled Annabel Sutherland.
Spinners Grace Scrivens and Kerr tightened Spirit's grip by attacking the stumps and pressure told when Bryce lofted the latter to long-on to end an enterprising knock. Thereafter only Carey broke the shackles, taking three fours off one set from Gibson, but Kerr returned to have her stumped by Mooney.
Their total of 119 looked light and Gibson, opening for the first time in the tournament, set about the chase with relish with some brutal hitting, including hoisting Carey for a glorious straight six.
An ugly tennis shot to a short ball from Sutherland looked to have ended the fun on 24, but Fire's luck was out as a no-ball was called. Gibson celebrated the reprieve by thrashing one from Alex Hartley to the long-off boundary to raise the 50 stand.
Mooney had played second fiddle to this juncture, but joined in the fun with a lofted drive over cover, before a cut shot bisected two fielders to the fence at third. By the time a repeat of the tennis shot proved Gibson's undoing, Spirit had 66 on the board and needed just a run a ball.
Sophie Luff, who might have been run out for nought, didn't stay long, but Mooney reached 50 with her ninth four as the hosts cantered home.