Gallery: Proteas down Bangladesh
Blog: StickyWicket gets the wobbles
Tendulkar came into Sunday's game needing just one more century to complete a hundred international hundreds.
But instead he was out for just two when, off the last ball of the first over of the match, Rampaul produced a brilliant lifting delivery on the line of off-stump that cut away and took the shoulder of the bat before going through to wicketkeeper Devon Thomas.
Australian umpire Steve Davis rejected Rampaul's raucous appeal, but a sporting Tendulkar walked off anyway to a stunned silence from a capacity Chidambaram Stadium crowd.
"It was the best ball of my cricket career," said 26-year-old Trinidad paceman Rampaul, who is of Indian descent.
"It was one of those moments in life you dream of. When I saw him walk I felt great. It was an amazing feeling. I wasn't sure how to celebrate.
"Here was I, in one of the biggest matches of my career, getting the wicket of one of the greatest batsmen. I felt really great to get such a massive breakthrough for the team," Rampaul added.
What made Rampaul's performance even more impressive was that this was his World Cup debut and, after replacing the ill Kemar Roach, he marked the occasion in style with career-best figures of five for 51.
Unfortunately for the West Indies, a batting collapse meant they still lost the match by 80 runs, but the result was good enough to secure a quarterfinal against Pakistan in Dhaka on Wednesday.
"I was happy to get into the team and play my part," Rampaul said.
"It was very exciting to play in front such a large crowd on such a big stage...I was happy to be able to make the most of my opportunity.
"The pitch had some extra bounce at the start of the India innings, and I knew if I got the ball in the right areas I would be successful," added Rampaul, whose previous best was four for 37 against India in Kingston in June 2009.
That win was the last time the West Indies beat a top nation in a one-dayer.
"Later in the innings I got the ball to reverse swing and I attacked the stumps. Things went in my favour and I felt good to get my first five-wicket haul in one-day cricket," added Rampaul.