Quinton de Kock's first international century of 2015 helped South Africa to an 18-run win over India, sealing a 2-1 lead in the five-match one-day international series.

Opening batsman De Kock looked in fine nick amid warm conditions in Rajkot and his knock included 11 fours and one six as the Proteas made 270-7, before Morne Morkel took four key Indian wickets to hold off their run-chase.

Faf du Plessis' also contributed 60 as part of a 118-run stand with De Kock for the third wicket.

Rohit Sharma (65), Virat Kohli (77) and captain MS Dhoni (47) - who made 92 in India's 22-run win on Wednesday - scored well and it appeared as though a thrilling chase was on the cards with India requiring 86 from the last 10 overs.

But the run-rate dried up as late wickets fell and some excellent bowling from Morkel (4-39) meant South Africa limited India to 252-6.

After the tourists won the toss and opted to bat, David Miller (33) - promoted to opener for just the third time in his career in a bid to boost his form - displayed neat footwork and found gaps in the field.

At the other end, De Kock was clinical against fuller deliveries and hit back-to-back drives off Harbhajan Singh (1-41) for four.

Harbhajan broke the partnership when Miller sliced to Ajinkya Rahane at backward point, and Hashim Amla (5) was stumped for the second straight match having struggled at number three. 

South Africa's rate dried somewhat but De Kock moved past 50 after facing 61 balls, before slogging Harbhajan over the covers in the 22nd over.

Du Plessis scored well and made the most of a life when he was caught of a Mohit Sharma (2-62) no-ball on 16.

With 15 overs remaining, De Kock brought up his century by bludgeoning Mohit through the covers for four, but Du Plessis was caught at short third man when trying a scoop shot off the right-hander.

Soon after, a tiring De Kock was run out when trying to steal a single and AB De Villiers (4) failed to make a telling contribution as India's spinners stifled the Proteas, to concede just 60 runs from the last 10 overs.

Shikhar Dhawan (13) nicked behind off Morkel but Rohit and Kohli built a fine partnership in India's reply - the duo finding particular joy against Kagiso Rabada (0-39) and JP Duminy (1-46).

Duminy caught and bowled Rohit with a clever shorter ball, but Kohli and Dhoni added 80 for the third wicket – the latter hitting the ropes five times.

But when Dhoni dabbed at one from Morkel that Dale Steyn snapped up at short third man South Africa regained the initiative and Suresh Raina was sent back for a duck.

And arguably the defining moment came when Kohli's knock came to an end when he launched Morkel to Miller at deep midwicket.

From there India's innings petered out as South Africa moved ahead in the series.