Virat Kohli looked in great touch during his brief 19-run stay but he too was undone by Rampaul's probing length outside the off stump.
While trying to leave a delivery at the last moment, the ball just brushed Kohli's bat on to the safe hands of wicket-keeper Johnson Charles.
But from there on it was a Dhawan-Yuvraj show as the duo went about its business in style and shared the run-a-ball century partnership.
Dhawan was the aggressive one among the two. The hallmark of Dhawan's innings was his elegant drives through the extra cover region and short-arm pulls.
Dhawan sent the West Indies bowlers' on a leather hunt and found the fence at will. He completely dominated the Caribbean attack and hit as many as 20 boundaries during his fiery knock.
By the time Yuvraj and Dhawan got out, they had ensured the series-clinching victory for India.
Yuvraj was caught by Dwayne Bravo at the slip off Sunil Narine in the 31st over but not before the left-hander reached his fifty which was laced with seven fours.
Dhawan finally departed in the 38th over, caught by Dwayne Bravo of his own bowling as the bat turned in his hand.
Dhoni (23 not out) and Ravindra Jadeja (2 not out) completed the formalities for India with consummate ease.
Dhoni's decision to bowl first after winning the toss did not yield the desired result as his bowlers could pick up just one wicket before Powell and Samuels joined hands to take West Indies forward.
Opener Johnson Charles (11) failed yet again when Bhuvneshwar Kumar went through his defence in the fifth over with a perfect inswinger leaving West Indies at 20 for one.
But thereafter Powell and Samuels got together and played sensibly, mixing caution with aggression to stitch a century stand for the second wicket and lay the foundation for a big total.
Both Powell and Samuels were cautious in their approach as they brought up the West Indies fifty in 11.3 overs.
Both the batsmen were content to see off the new ball in the morning. The duo kept rotating the strike with ones and twos and punished loose deliveries that came their