South East Stars 161 for 8 (Brits 85, Ballinger 3-26) beat The Blaze 159 (Graves 56, Davies 3-28) by two wickets
Brits, whose semi-final half-century helped end England's hopes in the Women's T20 World Cup in February, followed her 112 not out against Sunrisers by hitting 10 fours and three sixes in a 63-ball 85 to put the Stars right on the heels of second-placed Central Sparks in the table, which is currently led by The Blaze.
After a brief stoppage for rain, Stars needed to match The Blaze total in 48 overs according to a Duckworth-Lewis-Stern calculation and though there were some nerves as late wickets left them eight down, they eased across the line with 14 and a half overs to spare. Left-arm quick Grace Ballinger was the most successful Blaze bowler with three for 26.
The Blaze met early trouble after opting to bat first on what proved to be a lively pitch with three wickets lost in the opening seven overs with only 19 scored.
Marie Kelly, who began brightly with two boundaries off Davies, was leg before in the same over. Davies claimed a second when Georgie Boyce's uppish cut shot picked out backward point, before Kathryn Bryce lost her middle stump to MacDonald-Gay.
Sarah Bryce and Michaela Kirk added 31 in seven overs but when the latter was given out caught behind down the leg side off MacDonald-Gay, it sparked another clatter of wickets as England Under-19 all-rounder Stonehouse struck in consecutive overs, bowling Kathryn Bryce with a full delivery and having Nadine de Klerk, who had edged the previous delivery past slip for four, caught behind off another nick.
From 62 for six after 17 overs, The Blaze had much to do to post a total they could realistically hope to defend. Graves and Sophie Munro mounted something of a fightback, adding 65 for the seventh wicket either side of an hour-long stoppage for rain.
But both fell seeking to accelerate after Davies and Scholfield had shared four consecutive maidens, Munro holing out to mid-on before Graves, having completed her second List A fifty with her sixth boundary, was caught at mid-off.
Davies, so effective at the top of the innings, returned to york Lucy Higham, and Davidson-Richards had Grace Ballinger caught at cover as the innings ended in the 47th over.
Stars, whose batting line-up has proved one of the most potent in the 50-over competition this year, looked strongly placed at the halfway stage in the match but like The Blaze ran into early problems in their innings, stumbling to 30 for three in the powerplay.
Stonehouse, who had started assertively, chanced a single to backward point but was beaten by Kirk's brilliant direct hit, with fellow opener Kira Chathli caught at slip in the same over. Kirstie Gordon struck with her second ball as Bryony Smith was leg before to one that kept low.
Brits, watchful at first, launched into a flurry of shots to get the scoreboard moving in the Stars' favour, clubbing 24 runs in the space of eight deliveries, with two towering sixes and a swept four off Gordon and three boundaries off Kathryn Bryce.
Two quick wickets gave The Blaze renewed hope as Davidson-Richards was trapped in front by Bryce and Munro bowled Maddie Blinkhorn-Jones but after Paige Scholfield had been dropped at slip Brits went to a 43-ball fifty with a third six, hammered over long-on off Munro in a 20-run over, and it was clear the Stars would win so long as the South African was still there, with only 47 needed and 26 overs still in hand.
Scholfield fell for a streaky 19 when she top-edged Gordon to be caught at slip and Brits, who is on a short-term contract with the Stars, could not quite finish the job, Gordon holding a steepling catch at mid-off, but by that stage only five runs were needed for victory.
A superb catch by Kirk at gully to remove MacDonald-Gay off Ballinger induced some nerves for the Stars at 155 for eight, the overs in hand meant their ninth-wicket pair could bide their time before Davies took an opportunity to hit the winning boundary.