Shubhankar Sharma held his nerve to sign for a closing 69 and win a first European Tour title at the weather-delayed Joburg Open.
Heavy storms on Sunday forced the event at Randpark Golf Club into a fifth day, with Sharma holding a four-shot lead with his ball on the eighth green when the hooter sounded.
The Indian returned early Monday morning to make his par and he birdied the next hole before finishing with nine pars to finish at 23 under, three shots clear of South African Erik van Rooyen.
A place at next year's Open Championship was up for grabs for the top three players in the field not already exempt and South Africa's Shaun Norris grabbed his spot at Carnoustie due to his higher world ranking after finishing alongside Finn Tapio Pulkkanen at 17 under.
Sharma has five wins on the Professional Golf Tour of India but this is the 21-year-old's first victory on a major circuit after eight top-10 finishes on the Asian Tour.
"It feels absolutely wonderful to have won this week," he said at the trophy presentation. "I actually wasn't going to come here about a week ago and I decided to come so I'm really happy that I came. This is my first time in South Africa and I don't think I'm ever going forget my first time in South Africa.
"I hit the ball good and I putted really well but the key up-and-downs I made over the first three days, I think I only missed two up-and-downs over the whole week. Even today, the up-and-downs I made on the 10th, the 13th and the 15th were very crucial.
"Once in a while you just have to make a few par saves to get a round going and I did just that the whole week."
Van Rooyen was left with a tap-in on the ninth when he resumed his round and while he also birdied the 12th, he could not make any further progress as he signed for a 66.
England's Marcus Armitage was the leading British performer at 15 under, two shots clear of compatriot James Morrison and three ahead of another Englishman in Charlie Ford.