The 31-year-old won his national Open for the first time after an incredible 62 featuring eight birdies and an eagle
Branden Grace Wins South African Open
Related: Branden Grace What's in the bag? - South African Open winning clubs
The 2010 Open champion shot three under with a birdie, an eagle and 16 pars but will rue pars on all three of the par-5s.
Another great story from the week was that of Englishman Marcus Armitage who finished in 3rd.
The World No.1398 birdied the 72nd hole to finish 3rd alone and qualify for the Open Championship.
It was also a great week for 18-year-old amateur Jayden Trey Schaper who finished in T6th to win the low amateur honours.
"That was remarkable," Branden Grace said after his winning 62.
"I played flawless golf and I can't remember the last time the putter was that hot.
"This is the one I really wanted.
"This means so much to any South African, winning on home soil, the guys get so behind you and it's such an emotional feeling.
"It's the first win with the little one here so he's going to have a photo with the trophy and then it's a good birthday wish to my Mrs today, she's a birthday girl today so it's a good birthday present."
Watch highlights of Grace's final round -
2020 South African Open Leaderboard:
1 Branden Grace -21
2 Louis Oosthuizen -18
3 Marcus Armitage -16
4 Jack Senior -15
4 Jaco Ahlers -15
6 Hennie Du Plessis -14
6 George Coetzee -14
6 JC Ritchie -14
6 Andy Sullivan -14
6 Jayden Trey Schaper (amateur) -14
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