In yet another match in Trinidad severely affected by rain, the World Cup and Champions Trophy holders battled to 119 for three off 29 overs before a torrential downpour just before midday seemed set to force the match into a reserve day.
However the conditions improved significantly in late afternoon, and with the Sri Lankans set a revised target of 178 off 26 overs under the Duckworth-Lewis system, Bhuvneshwar Kumar produced an outstanding spell of seaming bowling, taking four for eight off his allotted six overs and ensuring that Sri Lanka were routed for 96 in reply.
India's 81-run margin of victory was also sizeable enough to ensure that while they finished level on nine points with both Sri Lanka and the West Indies, their net run-rate was superior to the Caribbean side's, so knocking Dwayne Bravo's team out of the competition and giving the hosts an unwanted two extra days to prepare for the five-match One-Day International Series with Pakistan, beginning on Sunday in Guyana.
Kumar exploited the helpful conditions masterfully, extracting pace and bounce off a greenish pitch and moving the ball both ways. "I feel proud to put in a performance like this for my country, especially in a match of such importance," he said, reflecting on his match-winning effort, the best by an Indian in One-Day Internationals at Queen's Park Oval.
"I really enjoyed bowling here, just as it was in England, so I just tried to bowl in good areas consistently." He accounted for Upul Tharanga and Kumar Sangakkara off successive deliveries in his second over, although Sangakkara could consider himself unfortunate to be adjudged LBW.
There was no doubt though about his other victims, Mahela Jayawardene slicing a catch to third man and Lahiru Thirimanne driving unerringly to Virat Kohli at cover. India's captain, who earlier in the day appeared thoroughly flustered by the challenging conditions, never allowed the Sri Lankans a way out of their dire straits, employing his support bowlers effectively.
Left-arm spinner Ravindra Jadeja accounted for skipper Angelo Mathews and topscorer Dinesh Chandimal (26) to ensure there was to be no miraculous revival. "To bounce back the way we've done and top the table after losing the first two matches really shows a lot of character," said a delighted Kohli in the aftermath of victory.
"It was all about playing smart cricket when we were batting to ensure we didn't lose wickets slogging. It worked out well for us with the help of the Duckworth-Lewis (method)." Rohit Sharma's patient, unbeaten 48 at the top of the order when India were put in was vital to holding the innings together on a bright but increasingly humid morning.
He lost the attacking Shikhar Dhawan in Mathews' first over while Herath once again proved his worth with the ball, the left-arm spinner trapping the struggling Kohli leg-before on the back foot and then bowling Dinesh Karthik. By the fall of that third wicket it became inevitable that a rain interruption was only a matter of minutes away.
Sharma and Suresh Raina ensured there were no further casualties before the showers descended and waited with their teammates in hope that they would have the chance later in the day to pull off the victory needed to get to the final. With the showers eventually relenting, their determination and the inspirational bowling of Kumar saw them through.