"It is a gift to be able to sing like that," Delta said, before Boy George cut her off to address Leo's history of being bullied at school.
"I went to school a long time ago," the 56-year-old vocalist said. "And in the '70s, people didn't hold back. I know all about that stuff. And look at me today."
Delta attempted to play nice, pointing out the teenager had just sung his heart out on national television and couldn't possibly make a wrong decision.
"Either of us will take care of you and make sure you shine," she said.
"You're obviously Australian, right?" Boy George shot back. "And you know Delta's the princess of Australia? You also know that I'm the queen of England. More importantly, I'm famous all over the world."
The audience erupted into gasps of shock, while Kelly Rowland admonished the British pop star for his comments.
"You know what I would say to that, my friend?" Delta replied. "I'm really proud of Australia and I'm really proud of what I've been blessed to do here. It is an honour to sing wherever you sing from."
Rowland then sat with Delta to make sure she was OK. The cameras even caught the Aussie star fighting back tears.
The fourth judge, Nick Jonas, summed up the tense situation when he remarked: "Do we need a boxing ring in here?"
Boy George's cutting remarks aside, Leo Abisaab decided to go with the queen of england.
Broede Carmody is an entertainment reporter at Fairfax Media.
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