Virat Kohli and Ajinkya Rahane shared a 189-run third wicket partnership to take India to a comfortable six-wicket win in the first one-day international against South Africa at Kingsmead.
Kohli made 112, extending his record of centuries in one-day run chases to 20, and Rahane scored 79 as India reached the victory target of 270 with 27 balls to spare.
"It was quite special," said Kohli. "The first game of the series is always important and we wanted to take the confidence of the last Test into here."
The innings was Kohli's 33rd one-day international century, moving him to within 16 of Sachin Tendulkar's all-time record of 49, and pushed his career average to 56.08, which is the highest ever among Test playing nations and more than two runs better than the next best, South Africa's AB de Villiers (54.06).
It was also his 20th century in a run chase, 18 of which have resulted in victories, and his average batting second is now 65.84.
"It's easier (batting second)," Kohli said.
"You can break down a total when you have a number on the board, you know exactly what you want to do against each bowler. It suits my game plan."
The India captain praised Rahane after their partnership took India to within 14 runs of victory before both fell to catches in the deep.
Kohli made his runs off 119 balls with ten fours, while Rahane struck five fours and two sixes in an 86-ball innings.
"He capitalised on that number four spot which we have been wanting to sort out for a while now," said Kohli.
India ended a sequence of 17 successive home wins by South Africa and comprehensively outplayed the team that went into the match as the top-ranked one-day international team.
Second-ranked India controlled most of the match despite a century by South Africa captain Faf du Plessis.
India’s decision to pick two wrist spinners paid off as Yuzvendra Chahal and Kuldeep Yadav shared five wickets and were mainly responsible for restricting South Africa to 8-269.
Du Plessis made 120 off 112 balls but it was only late in the innings that South Africa were able to lift their scoring rate on a slow pitch after slumping to 5-134 in 27.5 overs.
Du Plessis shared partnerships of 74 with Chris Morris and 56 with Andile Phehlukwayo for the sixth and seventh wickets.
"Those two wrist spinners have been the difference for us," said Kohli. "Breaking that middle order was very crucial."
Leg-spinner Chahal took 2-45 and left-arm wrist spinner Yadav took 3-45.
Du Plessis admitted: "We didn’t bat well enough. India bowled really well and we were 50 to 70 runs short."
There was a scare for India early in the South African innings when Kohli jarred his left knee when attempting a sliding stop on a soft outfield.
He left the field twice to receive treatment. He said he had also strained his groin.
"I’m fine for now," he said.