The Danes, who are ranked in just 34th spot in the world, were considered huge underdogs against the defending world champions, with bookmakers offering 12 times the money back in case of a Danish win.
The Danish duo were clearly on top in the third set, but nearly threw it all away before they sealed the match after a very dramatic end to the match.
The Danes led 18-12 and 19-14, but the world champions restored parity at 19-19, before Danish match points at 20-19 and 21-20 were squandered.
The Malaysian pair then had two match points saved before the Danes capitalized on the third match point when Chen Tang Jie hit the shuttlecock into the net.
Afterwards, the Danes did not doubt that it was their biggest result together ever.
"I am at a loss for words. That's what we play for. I was completely shaking when we signed autographs after the match", said Rasmus Espersen to TV 2 Sport, and was complemented by his partner.
"We didn't expect that at all. And that's probably how we felt throughout the game, and that's why we kept playing bravely. Probably also more courageous than usual", says Amalie Cecilie Kudsk.
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