The experienced pair of Charlotte Edwards and Claire Taylor rescued an experimental England line-up from an early wobble chasing South Africa's 158, to maintain their unblemished record this summer with a six-wicket win and ease to a 4-0 series lead.
With the series already secured, England sent in Beth Morgan and Jenny Gunn at the top of the order, instead of their usual places lower down, and the pair put on a solid 40 before England lost 4 for 18 mainly through Ashlyn Kilowan.
But although Kilowan finished with 3 for 19 - Gunn, Ebony Rainford-Brent and Laura Marsh - South Africa's attack couldn't penetrate the doughty defences of Edwards and Taylor who guided England home with an unbroken stand of 101. Taylor reached 37 not out, while the in-form Edwards caressed her way to 58. The other Taylor, Sarah, will have to wait another match to attempt her
world record, but she and England can afford to wait for it.
Earlier, Alicia Smith had provided substance for South Africa, making a solid 68 and Shandre Fritz added a handy 31, both falling to run-outs. England bowled well as a unit to systematically dismiss work their way through the line-up however, and there was a wicket on debut for 16-year-old Anya Shrubsole. Though Shrubsole opened the bowling, the pace bowler had to wait until the end to close the innings, as the tailender Marcia Letsoalo was snapped up by Isa Guha.
The series concludes at Chesterfield on Monday and South Africa will be encouraged by the determined batting shown by Smith and Fritz and their initial bowling efforts. But with England in such dominant form, the home side are well on course for the clean sweep.