South Africa sprinted to 147/4 in 15 overs when Klaasen smacked three sixes and a four in left-arm spinner Axar Patel’s over which cost India 24 runs.
But pace ace Jasprit Bumrah conceded only six runs off his next two overs and, in between, Pandya got the dangerous Klaasen caught behind.
David Miller couldn’t get the strike much despite scoring 21 and left-arm fast bowler Arshdeep conceded just four in the penultimate over. That gave Pandya a cushion of 16 runs to defend off the last over.
Off Pandya’s first ball, Miller was dismissed when Suryakumar Yadav plucked a brilliant juggling catch on the edge of the long-off boundary and sealed the result.
Earlier, Kohli, who tallied only 75 runs in seven games, made 76 off 59 balls with six fours and two sixes after India was in early trouble at 34/3 inside the first five overs.
Patel absorbed the pressure well after getting promoted at No. 5, hitting four sixes in his brisk 47 off 31 balls, and put India back on track by sharing a 72-run stand with Kohli.
Kohli completed his half-century off 48 balls in the 17th over, then accelerated by smashing big sixes against Kagiso Rabada (1/36) and Marco Jansen (1/49). Kohli holed out in the deep in the penultimate over.
Shivam Dube made 27 off 16 balls and fell in Anrich Nortje’s (2/26) last over as India scored 58 runs in the last five overs.
Kohli got India off to a flier when he hit left-arm fast bowler Jansen for three boundaries in the first over, and captain Sharma struck left-arm spinner Keshav Maharaj (2/23) for two fours off his first two balls.
But Maharaj struck twice in his first over when Sharma was brilliantly snapped up by Klaasen low at square leg, and Rishabh Pant hit off the toe-end of the bat while attempting a reverse sweep and ballooned a simple catch behind the wickets.
Klaasen shone again in the outfield when he caught Yadav at deep fine leg off Rabada’s short-pitched ball before Patel and Kohli rebuilt the innings.
Patel was run out off a brilliant direct throw from wicketkeeper Quinton de Kock as he smartly intercepted Kohli’s flick and then hit the stumps at the non-striker’s end.
