Rene Meulensteen serenaded the Socceroos into the last 16 - and then took a swipe at FIFA.
Manchester United 's former assistant boss took out the mic and blasted out a corrupted version of 'Sweet Caroline' to get Graham Arnold's men in the mood. And then the Aussies upset the form book and dumped out the Danes thanks to Mathew Leckie's goal-of-a-lifetime.
Dutchman Muelensteen, who spent six years by Sir Alex Ferguson's side as his assistant at Old Trafford, took his time before choosing his moment. He said: "When you are a newcomer, you have to do an initiation, right?
"We were in Turkey when our coach Graham Arnold said to me: 'Listen, Rene, you're going to have to sing as well'. I replied to Arnie: 'I will - but not today.'
"I mean, I'm okay, I get by. So, I pulled Vinnie - our chef - and he got a massive speaker and a microphone at our base. My party piece has always been 'Sweet Caroline,' by Neil Diamond.
"It always gets everyone going. I said: 'Listen guys, this is the song, you all know it but I'm changing the lyrics. It's going to be 'Sweet Socceroos,' that's what it's going to be.
"We sang that - it did the trick - it got everyone going. What's my next party-piece? I don't know. Is there a song called: 'I'm not going home yet?"
Meulensteen was overjoyed for veteran Aussie coach Arnold who now faces a stiff test to overcome Argentina on Sunday if the Socceroos want to create history by reaching the last eight.
Leckie's strike - the games are being broadcast in the middle of the night - created wild scenes back in Oz but the Dutch coach had bigger issues to confront.
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He said: "Do you realise the difference in qualifying in England or Holland between you and what we have to do?
"There are eight games - four away, four at home. We have ten group games, then another eight and if you don't qualify from that, you've got two play-off games.
"Never mind the distances we have to travel. So, my message to FIFA is: Make it a level playing field. How can it be that England or Holland play eight games and the furthest they have to travel is three-and-a-half hours?
"Look at us. If we are playing on Thursday, we have players flying in from all over the place. Some coming in on Monday, some on Tuesday. We have one training session and then everyone expects a world-class performance.
"It's not possible. Then you get on a plane, fly for 15 hours and everyone expects similar. It's impossible.
"It is what it is. But it cannot be fair that some teams walk into the World Cup after eight qualifying games and others have to play 20. It doesn't make sense to me."
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