|ICC Men's Cricket World Cup, Hampshire Bowl|
|South Africa 227-9 (50 overs): Morris 42, Chahal 4-51, Bumrah 2-35|
|India 230-4 (47.3 overs): Rohit 122*, Dhoni 34, Rabada 2-39|
|India won by six wickets|
|Scorecard; Table; Schedule|
Rohit Sharma scored an unbeaten 122 to guide India to a straightforward six-wicket win against South Africa in their opening World Cup match.
Chasing 228, opener Rohit guided India home with 15 balls to spare.
A fine bowling display had restricted South Africa to 227-9 with leg-spinner Yuzvendra Chahal taking 4-51.
Jasprit Bumrah and Bhuvneshwar Kumar took two wickets apiece as Chris Morris top-scored with 42 for the Proteas, who have now lost their first three games.
Two-time winners India - the last team to get their campaign under way, with the tournament a week old - put together a complete performance with bat and ball in front of a sold-out Southampton crowd of more than 18,500 after losing the toss.
While captain and star attraction Virat Kohli may have only made 18, brilliantly caught by wicketkeeper Quinton de Kock, Rohit showed patience and control in his 144-ball stay at the crease, including 13 fours and two sixes.
On another difficult day for South Africa, they dropped a seemingly regulation catch offered by Rohit on 107 as David Miller put him down at extra cover off Kagiso Rabada.
After a third straight defeat, the Proteas' quest to reach the semi-finals now appears to be almost a knockout scenario as they cannot afford any more slip-ups with six games to play, starting against West Indies at the same venue on Monday.
This is the first time they have lost three successive matches at a World Cup.
Their weakened bowling attack, ravaged by injuries to pace bowlers Dale Steyn and Lungi Ngidi, was unable to make regular inroads as Rohit registered his 23rd ODI century to move one ahead of Sourav Ganguly on India's all-time batting records.
India's bowlers impress
Under grey skies, South Africa's batsmen found themselves on the back foot from the off.
Hashim Amla and De Kock were both back in the pavilion inside six overs as the Proteas stuttered to 34-2 inside the opening 10 overs.
Faf du Plessis (38) did not find life any easier as he had to fend off two rising deliveries from Hardik Pandya early in his innings, but he and Rassie van der Dussen (22) did apply themselves to add 54 for the third wicket.
However, Van der Dussen was the first to succumb to India's spin trio who began to tighten the squeeze in the middle overs.
Chahal's opening over removed both set batsmen before JP Duminy was trapped leg before by Kuldeep Yadav to reduce South Africa to 89-5.
While both David Miller (31) and Andile Phehlukwayo (34) fell after showing some determination, South Africa's most profitable partnership came for the eighth wicket - Morris and Kagiso Rabada adding 66 in 62 balls to push them towards their eventual 227-9.
For India, every option to which Kohli turned came up trumps.
Bumrah set the tone in a terrific opening spell which returned 2-13 from five overs and bagged Amla and De Kock with superb outswinging deliveries edged to second and third slip respectively.
Kumar and Pandya also proved tricky with the new ball and returning at the death, but the spinners Chahal, Kuldeep and Kedar Jadhav took a combined 5-113 from their 24 overs.
Chahal's 4-51 are the best figures so far in the tournament from any bowler who has completed their full allocation of 10 overs.
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Kohli falls to the spectacular but Rohit stays cool
Before this game, there was talk of an apparent falling-out between India captain Kohli and South Africa pace bowler Rabada.
Rabada was quoted as describing Kohli as "immature" following an exchange in an Indian Premier League game last month, but the right-hander was seemingly unperturbed by the speculation both before and during the game.
There was a brief passage of play when Kohli first came to the crease where Rabada bowled at full tilt, including a 90mph bouncer first ball, but it was his team-mate Phehlukwayo who claimed the prized wicket.
Wicketkeeper De Kock's superb diving catch, at full stretch to his right, sent Kohli on his way for 18 to leave India 54-2 in the 16th over.
However, the unflappable Rohit took up the baton to steer India's reply over the line.
He survived early scares as top edges off Rabada and Morris evaded the slips, while South Africa failed with an lbw review when he had 24.
Rohit's half-century came off 70 balls as he and KL Rahul (26) provided a steady platform in a third-wicket partnership of 85.
When Rahul fell tamely to a mistimed drive to mid-off, MS Dhoni (34) slotted into the support role with minimum fuss.
A simple push down the ground for a single off spinner Tabraiz Shamsi took Rohit to 100 off 128 balls, his second ton in his past three ODIs against South Africa, and sparked colourful crowd celebrations.
That passionate support will undoubtedly be out in force again on Sunday when India face Australia in their next game at The Oval.
'That was Rohit's best ODI innings' - what they said
India captain Virat Kohli: "It was a very professional effort from us in a low-scoring game and that was because of the way the pitch was throughout.
"We're pretty happy with how we played and starting well is always important. We really built the game nicely from the first 10 overs and finished it very professionally.
"This is by far Rohit's best ODI innings as he dealt with the pressure and the situation well after some short bowling he had to fend off early on.
"He was very composed and having played so many games, we expect that sort of maturity and calm from him. At no stage did we feel like he was going to throw it away.
"He played the perfect innings for that sort of situation on that wicket."
South Africa bowler Chris Morris: "To the fans at home, all I can say is stay with us. Stranger things have happened before in sport and we will do everything we can to make it happen.
"Our body language let us down in the first two games, which we addressed as a team. I thought today we stayed in the fight more."
Ex-England batter Ebony Rainford-Brent on BBC Test Match Special: "South Africa have not looked at the races at all since they arrived, but India have shown they mean business.
"From the opening bowlers, the spinners squeezing in the middle and the batsmen chasing it down, it was an all-round solid team performance.
"This is the way you want to start a tournament. For South Africa there is a lot of pain."