They both had big smiles on their faces as they performed the intimate routine.

After the track had ended she thanked her fans for turning out before leaving the stage.

Despite Mariah’s huge popularity and success, Radar reported that she struggled to sell out her eight date residency in February.

A source said: “Every high roller and whale who’s flying into Vegas is being given free tickets to her show.

5Mariah, 49, sang her hit Hero as dancer Bryan, 36, wrapped his hands around her waistCredit: Splash News5Diva Mariah went through a number of costume changesCredit: Splash News

“They’re being handed out at sports books, included in room service bills and slipped under doors all over the hotel.”

However, reps for Mariah denied that was the case.

Mariah and Bryan have been an item since December 2016.

They hooked up just months after Mariah split from billionaire businessman James Packer, 52.

The pair have been professionally linked for years, with Brian first taking to the stage with Mariah on her Adventures of Mimi tour in 2006.

Speaking to E! News about his early career with the songstress, he said: “She saw something in me that I actually didn’t recognize at first, from that it was over.

5She performed hit after hit in Sin CityCredit: Splash News5Mariah sang on a chaise longueCredit: Splash News

“It was set in history that we were gonna be connected some way, somehow.”

He has since been promoted to her creative director.

His skills were first recognised when he was cast as a backing dancer for Beyonce.