Northern Diamonds 140 for 8 (Armitage 82, Cooper 3-12) beat South East Stars 138 for 7 (Capsey 71, Hall 3-20) by two wickets
Captain Hollie Armitage
's career-best knock in the Charlotte Edwards Cup rescued Northern Diamonds from a sticky start against South East Stars as they triumphed by two wickets in a last-ball thriller.
Armitage top-scored with 82 from 59 balls at the Kia Oval, her second half-century of this year's competition, to secure her side's third straight victory after losing both openers with just six on the board.
The Diamonds skipper's efforts outshone those of Alice Capsey
, who had smashed 71 from 48 - also a personal best in the tournament - after being dropped twice, on 15 and 32, to hold Stars' innings together with a display of powerful hitting.
But their total of 138 for 7 was not quite enough, despite an excellent spell of 3 for 12 by off-spinner Claudie Cooper
and Lizzie Scott
sliced the final ball from Alice Davidson-Richards over point for four as Diamonds edged home.
Put in to bat, the Stars were soon in trouble as they lost both openers in the powerplay - Chloe Tryon taking a midwicket catch to remove Sophia Dunkley off Grace Hall
's bowling before a reversal of the roles signalled Bryony Smith's departure.
With Tash Farrant holing out to deep square leg, the home side were floundering at 33 for 3 and Diamonds turned the screw with a miserly mix of seam and spin that did not yield a single boundary in six overs.
But Capsey capitalised on her first life - with Hall unable to hold on, stretching at mid-off - by smashing successive fours off Katie Levick and using her feet to crack the spinner over the top for six.
Capsey was put down again by Leah Dobson at deep midwicket and, although the fielder took her next opportunity, pouching a skier to remove the dangerous Paige Scholfield and bring Hall a second wicket - the damage had been done.
The seamer finished with 3 for 20, helped by Abi Glen's smartly-taken catch at square leg to dismiss Davidson-Richards, but Diamonds were unable to get rid of Capsey until Glen had her taken at long-on in the final over.
Capsey helped to maintain Stars' momentum at the start of the visitors' reply, clinging on at mid-off to collect the prize scalp of Lauren Winfield-Hill, just after Dobson had perished to Freya Davies' pinpoint throw from square leg.
However, Armitage counter-attacked, punching Scholfield's first ball to the cover boundary and dominating her third-wicket stand of 49 with Sterre Kalis - eventually broken when Dani Gregory pierced the latter's defences for 18.
Bess Heath proved a capable foil for Armitage, dispatching Smith to the fence twice in an over to reach 19 from 18 - and the Stars skipper was left to rue missing the chance to prise out her opposite number, shelling a mid-off catch off Cooper.
Armitage was eventually stumped off a Davies wide with eight required from nine deliveries, but Scott held her nerve to dispatch Davidson-Richards over the infield and clinch victory for the visitors.