Dane van Niekerk struck 63 off 43 balls as South Africa Women set up a series decider with a 17-run win over England Women on the Duckworth-Lewis method in the rain-hit second T20 at Newlands.
Van Niekerk and skipper Mignon de Preez (47no) propelled the hosts to 145-3 off 17.2 overs before bad weather interrupted the match for the second and final time.
Sarah Taylor's 66 off 52 balls - her 14th T20i half-century and second in as many games - had earlier steered England Women to 156-6 off their allocation.
Taylor anchored England's innings after the visitors were put in, sharing stands of 59 and 63 with Charlotte Edwards (34 off 22) and Heather Knight (29 off 20) respectively after the early loss of Tammy Beaumont.
She pushed on after Edwards was bowled off-stump by Sune Luus (2-26) attempting to reverse sweep, reaching her fifty off 43 balls having been dropped by Chloe Tryon on 35.
Knight offered bold support, striking the first six of the game over wide long on to take England to 107-3 off 15 overs before she picked out Marizanne Kapp in the deep off Shabnim Ismail when trying to clear the rope again.
Taylor failed to bat through the innings when she was run out in a final over costing just four runs while attempting to come back for a second off Ismail, Jenny Gunn suffering the same fate two balls later.
South Africa, like England, accumulated 52-1 off their first six overs - Trisha Chetty the sole casualty, run out after a horror mid-pitch mix-up with Van Niekerk.
England had chances to remove Van Niekerk early but the opener was put down by Gunn on six and Edwards on 22.
The 22-year-old struck the ball crisply all around the wicket to bring up her fifty off 34 balls, posting her fifty-run stand with Du Preez off 40 balls.
But with the pressure building on England, Van Niekerk advanced looking to hit Rebecca Grundy down the ground and was stumped by Taylor to break a 68-run stand.
The hosts were ahead of the Duckworth-Lewis target - needing 49 runs off 42 balls to win - when rain brought a 10-minute break, South Africa on 108-2 off 13 overs at the time.
On the restart Du Preez picked up where she left off, getting the chase down to less than a run-a-ball with four overs left as the 16th over - bowled by Shrubsole - cost 14.
Kapp whipped Georgia Elwiss for six to keep the momentum up before falling lbw to the spinner and when rain returned, the hosts still had the edge, needing just 12 off 16 balls.
Watch the third T20 between South Africa Women and England Women live on Sky Sports 2 from 7.55am on Sunday.