Rishabh Pant hit 85 off 71 balls as India posted 287-6 in the second ODI at Boland Park on Friday.
The left-hander made batting look easy on a slow pitch, striking the ball to all parts of the ground and on several occasions taking one hand off his bat as he hit the ball. Pant hit 10 fours and two sixes.
Rahul made 55 off 79 balls and shared a third-wicket partnership of 115 with Pant.
But Rahul was dropped twice and the stand should have been broken after the pair had added only six runs when an easy run-out opportunity was botched with both batsmen at the same end of the pitch.
Shardul Thakur (40*) and Ravichandran Ashwin (25*) scored freely in an unbeaten seventh-wicket stand of 48 in the last six overs as the bowlers wilted in heat which reached 40C towards the end of the innings.