Seeded fifth, the Indian took 57 minutes to see off 10th seed Chun Seang Tan of Malaysia 21-16, 14-21, 24-22 in an edge-of-the-seat semifinal encounter to set up a summit clash with top seed Indonesian Dionysius Hayom Rumbaka.
It was a closely fought contest, between the two at the Tan Binh Sports Center as the lead changed hands frequently in the decider after both Prannoy and Tan pocketed one game each.
However, in the end it was the Indian who held his nerves in crucial moments to have the last laugh.
The silver medallist at the 2010 Youth Olympic Games, Prannoy has stunned top Indian players such as Parupalli Kashyap and Ajay Jayaram.
He also claimed victory over top players such as former World and Olympic champion Taufik Hidayat of Indonesia and Thailand's Boonsak Ponsana.
Image: HS Prannoy
Photograph: Robertus Pudyanto/Getty Images
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