If his seven-shot victory in the British Open felt like a dream, reality arrived when he awoke Monday.
"I put it next to my bed last night, and I woke up this morning and I looked at it, and I immediately grabbed the phone and text Chubby Chandler, my agent, saying, 'I've got this funny old jug next to my bed.'
"Man, oh, man," he said. "That was special waking up next to it."
Equally special was his victory at the home of golf, a performance so pure that he never trailed over the final 48 holes and hit into only one bunker on the Old Course, on the 14th hole Sunday when the championship had already been decided.
Oosthuizen became the fifth player in the past six Grand Slam events to win his first major, and the question sure to follow is whether he is capable of winning more or if he happened to play his best golf during an important week.
The margin of victory is what makes this stand out.
Until his conservative play on the 17th to make bogey, Oosthuizen was poised to tie the Open record over 72 holes with an eight-shot victory, last achieved by Tiger Woods a decade ago.
Seven shots is no less impressive. In the 150 years of major championships, only 14 players have won by seven shots or more (Woods has done it three times, Jack Nicklaus twice). Of those players, only two -- Fred Herd in the 1898 U.S. Open and Willie Smith in the 1899 U.S. Open -- never won another major.
Where does Oosthuizen fit in?
"Every great Open champion has to win for the first time. And I for one would not be surprised to see him win again," Royal & Ancient chief executive Peter Dawson said Monday.
That would be the plan for the 27-year-old South African.
In this age of players turning pro earlier and winning tour events immediately, from Ryo Ishikawa to Rory McIlroy to Anthony Kim, Oosthuizen might be a late bloomer.
Ernie Els noticed his skill immediately when he invited Oosthuizen to be part of his foundation, which helps promising juniors who need financial assistance. Oosthuizen wears "57" on his sleeve, the name of his own foundation, as a tribute to the score he shot on his home course of Mossel Bay along the Garden Route in South Africa.
"The wind blows so hard there that the sea gulls walk," Chandler said.
The key to his victory came in the second round. Oosthuizen began in the wind and rain, and he has never liked playing in wet weather. He managed to get through the rough part without dropping a shot, and wound up with a 67 just as the wind turned fierce.
He figures the seven years he spent on the European Tour toughened him up, and winning in Spain for his first European Tour title did nothing but boost his confidence.
"I want a few more of these," he said, his eyes rarely wandering from the jug. "I think winning one just wants you to get to the second one, and winning a second one and then get to the third. Yeah, I'm going to work a bit harder probably from now on and just try and get up there with as many majors as I can."