George Coetzee produced a putting masterclass to move himself to the brink of a second Tshwane Open title before storms arrived in Waterkloof.
The South African is a member at Pretoria Country Club and entered the final round with a two-shot lead, although he found himself two behind Finn Mikko Korhonen after two early bogeys.
He then birdied five of his next eight holes, needing just ten putts to get to 18 under and lead Korhonen by three before the hooter sounded due to thunder and lightning at 3.37pm.
Coetzee was stood on the 16th tee when play was suspended, with Korhonen ahead on the green.
Play was due to resume at 5.15pm.
Should Coetzee hold on to take the title, it would be his fourth win on the European Tour - all of them coming on African soil.
Korhonen was a runner-up here last season and he still held some hope of claiming a first win at the 140th attempt.
South African Daniel van Tonder fired a 65 to set the clubhouse target at 14 under and was one clear of Chilean Felipe Aguilar and Frenchman Sébastien Gros - who were both playing the last - and Coetzee's playing partner Sam Horsfield.
