Robert Irwin joins US pop star Alex Warren on stage at Brisbane show in surprise appearance

American singer Alex Warren has shocked fans in Brisbane by welcoming national hero Robert Irwin onto the stage at his show on Wednesday.

Touring Australia with his Finding Family on the Road World Tour, the Ordinary singer had earlier played three concerts in Sydney, with stops in Melbourne, Adelaide and Perth still to come.

To the delight of Queensland fans, Irwin was invited to join him to press the “confetti button”, a tradition in which a fan or special guest is called upon to push a large button placed on stage that triggers an explosion of confetti to signal the end of his shows.

Irwin shared the vision to his socials, which saw him embrace Warren during a raucous response from the audience.

Pressing the red button centred on a brown pedestal, the animal conservationist continued to receive cheers as he jumped up and down alongside the singer who performed Fever Dream, while the two were blanketed by a confetti haze.

Before leaving the stage, Irwin offered fans an up-close look at his signature dancing skills, dropping to the floor to do the worm.

“I did the thing!!!!” Irwin captioned a clip of his experience, telling Warren, “Cheers mate!”

Fans expressed their delight at seeing the animal-lover leave his natural habitat of Australia Zoo, his base when in Queensland, and suggested he and Warren were a perfect match.

The appearance is not the first time the US Dancing with the Stars winner had been a celebrity guest on stage for a musician, with the star being invited by Role Model to bust a move alongside him in February at Laneway Festival in Perth as he performed viral hit Sally, When the Wine Runs Out.

“Who else in the world has been sally AND fever dream confetti presser!!!!!” one fan asked.

Noting Irwin’s tendency to pop up around the world unannounced, others admitted they were no longer shocked by his globe-trotting exploits.