After Sunday's opener in Dharamsala was washed out, the home team did well with the ball to restrict the Proteas to 149-5, Quinton de Kock top-scoring with 52.
Not for the first time in his career, Kohli timed the chase superbly, keeping the run-rate under control before accelerating late on to see his team cruise over the line in Mohali with six balls to spare.