Thoroughly outplayed by the Dutch in their Group E opener, the abject Danes seemed headed for an early World Cup exit after falling behind to a Samuel Eto'o goal in Saturday's game against Cameroon at Loftus Versfeld.
Then came the transformation.
Ponderous plodding became sleek invention. Counter-attacks once timid and toothless suddenly grew sharp and incisive, putting the bite on Africa's Indomitable Lions.
While Cameroon dictated the play, it was Denmark who grew in confidence as the game wore on, scoring two excellent goals through Nicklas Bendtner and Dennis Rommedahl to send the Africans crashing out of the tournament.
The result also sealed Netherlands' place in the second round and set up a showdown between Denmark and Japan in the final group game in Rustenburg on Thursday to determine who joins the Dutch in the last 16.
Denmark coach Morten Olsen displayed dual emotions after the match, almost tearing his hair out at his side's amateurish errors but lauding their heroic fighting spirit.
"We had far too many elementary mistakes. I can't allow that from our players," he told a news conference after the match.
"We must correct that so I wasn't happy actually.
"But the players fought heroically, some of them didn't play well today but they did fight," he added.
"It was a heroic physical effort but if we want to progress in this tournament we have a lot to work on."
While the Danes have their destiny in their own hands, they will not have an easy ride against Japan, supposedly the weakest team in the group.
"Supposedly," said Danish winger Jesper Gronkjaer.
"If you saw the game against the Dutch they were very well organised. There are no easy teams at the World Cup."
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