Shubhankar Sharma will have to wait until Monday to try to seal his first European Tour win after storms in South Africa sent the Joburg Open into a fifth day.
The Indian will take a four-shot lead into the extra day, with his final act on Sunday putting a solid tee-shot on to the par three eighth green before play was suspended at 1300 local time.
He had already made birdies on the second and sixth at that point to get to 22 under and lead the way from charging South African Erik van Rooyen.
"I'm going to treat it like another day," Sharma told europeantour.com. "I'm going to do the same things which I've been doing the last four days.
"It is not frustrating but you get into a groove when you start and you don't want to come off. I saw the clouds coming on the seventh hole and I was praying we could finish but we can't help it. I'm playing well so I want to continue doing that."
Van Rooyen started the day six shots behind Sharma but made birdies on the third, fourth, fifth and seventh and was looking at a tap-in on the ninth for another gain when the hooter sounded.
The initial delay was due to the threat of lightning but when the storm clouds arrived at Randpark Golf Club they brought with them heavy rain and hail, with play eventually abandoned for the day at 1730.
Van Rooyen was four shots clear of England's James Morrison and Finn Tapio Pulkkanen but the chasing pack had plenty to play for, with the top three players at this event not already exempt earning a place at next season's Open Championship.
Morrison was level par for the day playing in the final group alongside Sharma, while Pulkkanen had completed eight holes alongside Van Rooyen.
England's Marcus Armitage was in the group at 13 under having played eight holes, two shots clear of countrymen Mark Foster and Ross McGowan.