England 137 for 4 (Beaumont 34, Bouchier 33, Dercksen 2-22) beat South Africa 135 (Tryon 45, Dean 4-45, Ecclestone 3-27, Filer 3-32) by six wickets
Charlie Dean became the first England bowler to claim a hat-trick in a women's ODI for 25 years - though later admitted she hadn't noticed the feat - as South Africa were routed by six wickets at Kingsmead.
Having lost the opening ODI in Kimberley by six wickets on Wednesday, England bounced back to level the series in style, instigating a collapse of five wickets for four runs before an aggressive batting display led by Tammy Beaumont and Maia Bouchier wrapped up the contest with 26 overs to spare. After a 3-0 win in the T20Is, England have also claimed an unassailable 8-2 lead in the multi-format series.
After winning the toss and bowling first, England showed their intent from the outset, with Lauren Filer bowling both Tazmin Brits and Sune Luus in her first two overs to reduce South Africa to 14 for 2.
However, Laura Wolvaardt - in her 100th ODI - and Annerie Dercksen responded with a fluent stand of 58 in 13 overs to give the impression that South Africa had weathered much of England's early storm.
Then, however, came a drinks break at the end of the 16th over, and what followed was a stunning mid-innings meltdown.
On 29, and just three balls after the resumption, Dercksen sliced an open-faced drive off Dean to Filer at backward point, and with her sixth ball of the same over, Dean bagged the key blow of the innings, as Marizanne Kapp drove impulsively through the line and scuffed a simple catch to Sophie Ecclestone at mid-off.
Ecclestone herself was into the action four balls later, as Wolvaardt - whose cover-driving had once again been the feature of her innings - this time misjudged the length and inside-edged onto her own stumps for 35, as she hung back in the crease.
At 76 for 5, South Africa were punch-drunk, and two balls into Dean's next over, they were all but out for the count. Nadine de Klerk climbed into a horrible off-balance hack, which Heather Knight at slip scooped up via a deflection off the keeper's gloves, and then Sinalo Jafta pressed forward without conviction, and was pinned in front of middle and leg first-ball.
A review couldn't save her, and Dean had become only the third England bowler to claim an ODI hat-trick in women's cricket, after Carol Hodges against Denmark in 1993, and most recently Clare Connor against India in 1999. She looked nonplussed when quizzed about the achievement during the innings break, and later admitted at the post-match presentation that the moment had passed her by completely.
South Africa found some resistance, thanks to Chloe Tryon, who marshalled the lower-order with a hard-fought 45 from 49 balls. Filer returned to the attack to bowl Nonkululeko Mlaba as she retreated to leg, but her extra pace proved more to Tryon's liking, as her subsequent over was picked off for three fours through the off side.
The spinners, however, would not be denied for long. Ecclestone found some extra turn and bounce to prise out Tryon via a sharp take from Beaumont at short leg, and then mopped up the innings with 18 overs left unused as Ayanda Hlubi was bowled for 6.
In reply, England's chase was kickstarted by Beaumont and Bouchier, whose opening stand of 69 in 12 overs broke the back of the requirement.
Both were eventually done in by the aggressive Dercksen, whose use of the short ball induced two fluffed pulls, Bouchier to midwicket and Beaumont to the keeper, and when Heather Knight was trapped lbw for 7 by Kapp, there was the threat of a wobble at 82 for 3.
Danni Wyatt-Hodge and Nat Sciver-Brunt put the contest beyond any doubt, however, with a fourth-wicket stand of 47, and though de Klerk grabbed a consolation lbw in the final over, two fours from Amy Jones sealed the deal.
