England took control of the one-off Test against South Africa as the hosts lost their last seven first-innings wickets for 44 runs in a dramatic evening session.
The Proteas’ top order battled to reach 237-3 in Bloemfontein, before a delay for lightning after tea coincided with a change of course in the game.
England’s seamers pounced with the new ball under darkening skies to dismiss South Africa for 281 and take a 114-run lead.
That advantage was extended to 145 as Tammy Beaumont and Heather Knight steered England to 31-1 at the close, after first-innings centurion Maia Bouchier fell for a duck.
South Africa earlier appeared on course to reach parity through Marizanne Kapp, who made a fluent 57 before she was bowled by debutant Ryana MacDonald-Gay which sparked the collapse as the delay came just five balls later.
MacDonald-Gay struck again shortly after the resumption with Nadine de Klerk caught behind for a duck, Lauren Filer ended Sune Luus’ resistance for a gritty 56 and Chloe Tryon tamely chipped Lauren Bell to mid-on for 20.
Bell finished with 4-49 after mopping up the tail, with the collapse distracting from the disciplined efforts of South Africa’s top order throughout the morning and afternoon sessions.
Opener Anneke Bosch fell in the second over of the day, but a stand of 92 between Laura Wolvaardt and Annerie Dercksen helped the hosts rebuild until the latter was caught at slip off Filer from the final ball before lunch.
The omission of the decision review system (DRS) for the match had a huge impact on the home side as captain Wolvaardt was visibly frustrated to be given out lbw to Sophie Ecclestone for 65, suggesting she had hit the ball.
A chanceless partnership of 99 between Kapp and Luus followed but, once broken, a fragile middle to lower order was exposed and gave England hope of a first Test win since 2014.