Though he was late to rise to the occasion, Ramandeep (4th, 31st minute) displayed his finishing prowess by scoring twice at the Major Dhyan Chand National Stadium.
Apart from Ramdeep, drag-flick specialists Amit Rohidas (7th minute) and Gurjinder Singh (40th) were India’s other scorers.
Argentina's goals came from the sticks of Lucas Martinz, in the 38th minute, and Lautaro Diaz, in the 69th.
The India-Pakistan play-off match is on Saturday.
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Earlier, Pakistan defeated South Africa 4-0 in their 9-12th classification match.
Argentina will play South Africa in the 11th-12th place classification game on Saturday.
Out of the reckoning, the Indians came out like wounded tigers and dominated the exchanges in the opening half. They controlled the proceeding from the start and surged ahead in the fourth minute through
Ramandeep, who after receiving a through pass from Rohidas, dodged past an Argentine defender to score from the right corner of the circle.
Three minutes later, Rohidas doubled India's lead by converting the first penalty-corner awarded to the hosts with a grounded flick.
Argentina's best moments came in the middle of the opening period when they earned two back-to-back penalty-corners but India's defence was up to the task.
Ramandeep was once again at the thick of things when he scored a brilliant field goal in the 31st minute after dodging past three Argentine defenders to help India go into the breather with a three-goal cushion.
India were slow to get off the blocks after the crossover and Argentina utilise the moment by pulling one back three minutes into the second half.
Martinez beautifully deflected in skipper Gonzalo Peillat's pass from midfield to make the scoreline 3-1.
But it did not take India too long to restore their three-goal lead as Gurjinder converted a penalty-corner soon.
Argentina had their chances but lacked in execution as they wasted another penalty-corner.
India too wasted quite a few scoring opportunities, which included two from penalty-corners.
The scoreline could have been more convincing for the Indians but the woodwork denied Malak Singh in the 63rd minute.
Argentina reduced the margin of defeat a minute from the hooter through Lautaro Diaz's field goal.
Meanwhile, in other classification encounters of the day, England thrashed Egypt 6-1, while Spain scrapped past Canada 3-2.
England will lock horns with Spain in the 13-14th place play-off match while Egypt and Canada will square up to avoid the wooden spoon in the 16-team tournament.
Image: Ramandeep Singh scores India's opening goal against Argentina
Photograph: Hockey India
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