Los Angeles, Dec 16 : Legendary musician Madonna well and truly got 'Into the Groove' with her toyboy lover Josh Popper, after inviting him to join her on stage in New York. Mixing business with pleasure, Madonna turned up the heat with her younger boyfriend on the first US date of her epic Celebration tour, reports 'Mirror.co.uk'. Romance was in the air at the Barclay Center, in Brooklyn, when Madonna planted a kiss on 30-year-old Popper's cheek in front of the 14,000-strong crowd. The boxing coach and model made an unexpected appearance during the Vogue segment of the show, titled 'Estere's Ball' after her 11-year-old daughter. As per 'Mirror.co.uk', Madonna and her boyfriend sat beside one another and held up score cards as dancers performed sexy ballroom-style moves on a catwalk. Whilst the music icon sparkled in a black-and-silver bustier, teamed with opera gloves and heels, Popper opted for a simple T-shirt, shredded black pants and trainers. Afterwards, Madonna posted a picture of herself and Josh clutching '10' scorecards on Insta Story, with the caption: '10's across the board'. He was the latest surprise guest, following hot on the heels of FKA Twigs, Donatella Versace, Julia Fox and Diplo. Madonna fell for Popper, who owns a gym in the Big Apple, after hiring him to coach one of her children. They went Instagram official in February. /IANS