Katie Levick’s early wickets set Yorkshire Diamonds on the way to only their second win of the Kia Super League season.
The Sheffield-born leg-spinner removed Bryony Smith and Sarah Taylor in her first two overs – setbacks from which defending champions and hosts Surrey Stars never really recovered as they fell to a third successive defeat.
For the second week running, Stars posted a below par score of 121-6 and with Alyssa Healy (38) and Jemimah Rodrigues in the runs, Diamonds knocked off the target for the loss of five wickets with one ball to spare.
With two games against group leaders Western Storm still to play, Stars’ hopes of taking the defence of their crown through to finals’ day at Hove on September 1 look to be fading.
Surrey’s top-order batting woes continued after Diamonds’ skipper Lauren Winfield won the toss and put them in.
Smith was bowled by the third ball of the match from Levick (2-13), who struck again her next over, luring Taylor down the pitch to be stumped by Healey.
And Nat Sciver’s lean spell continued when she nicked a wide one from Katie George through to the wicketkeeper.
Lizelle Lee stood firm amid the carnage, hoisting a big six in an attempted counter-attack. But her aggression was cut short when she lifted Alice Davidson-Richards into the hands of Hollie Armitage at deep mid-on, leaving Stars 52-4.
Levick and George (1-20) kept the pressure on, meaning South African skipper Dane van Niekerk (32) and fellow country woman Marizanne Kapp (39 not out) had to rebuild carefully in a stand of 59 for the fifth wicket.
Both were dropped and hit sixes in a late bid to accelerate, Van Niekerk’s disappearing into the trees behind the scoreboard, but 121-6 looked light.
Healy and Winfield raced to 22 in reply, but Kapp (1-18) made the breakthrough with a lifting ball which the latter edged through to a diving Taylor.
Healy though continued to attack, hitting Mady Villiers for four boundaries in two overs, before lofting Sciver into the deep where Aylish Cranstone could only parry it over the ropes for six.
The Australian reached 38 out of a score of 62-1 before mistiming a drive off Amy Gordon (1-13), which Laura Marsh caught diving forward at mid-off.
Elation though would turn to despair for Gordon in the following over when she spilt an easy catch at mid-on to reprieve the new batter Rodrigues.
If that was the worst of Stars in the field, Bryony Smith produced the best with a direct hit to run out Armitage for 24,
Tight overs from Sciver and Laura Marsh followed to drag the game into the last over.
Alice Davidson-Richards and Katie Gordon both holed out off Marsh (2-15) going for the winning hit, to crank up the tension.
But Rodrigues (42 not out) left Stars to rue dropping her earlier by striking the winning boundary.