South Africa have now taken an unbeatable 2-0 lead in the five-match series. The first game a week ago was washed out.
Scorecard of 3rd ODI
Kemp's 100 not out was the top score as South Africa rallied from 76 for six to a total of 274 for seven. Pollock took four for 26 to help dismiss India for 168 in 41.3 overs.
Captain Rahul Dravid's 63, which he scored off 103 balls with four fours and a six, was the best of India's batting.
Kemp, who came to the crease at 71 for five and survived chances on nine and 34, faced 89 balls and hit six fours and seven sixes in an innings of effortlessly wielded power.
The 138 runs that Kemp and Andrew Hall, who scored 56, shared in an unbroken stand was a world record for the eighth wicket.