Maria opted for a bright pink zip-up jumper with a neon green band and black shorts, while Adelaide native Thanasi kept things cool in a white Nike logo T-shirt.It’s a long-standing tradition that always delights the hard-working ballkids of the Australian Open. And on Tuesday, when the 380 highly-trained youths gathered at the Rod Laver Arena in Melbourne for the inaugural group photo, they were blown away when Russian tennis champ Maria Sharapova, 27, and talented Australian teenager Thanasi Kokkinakis, 18, decided to join in on the Din976 fun.’ Later the enthusiastic crowd launched their tennis balls towards the cameras, with everyone erupting into a fit of laughter. Hello @AustralianOpen ballkids.jpg It’s a long-standing tradition that always delights the hard-working ballkids of the Australian Open. Hello Rod Laver Arena. The pair posed for a series of happy snaps and even enlisted the help of a selfie stick to try and squeeze everyone in the frame.Swamped in a sea of orange, the two professional players would have blended into the crowd if it wasn’t for their choice of clothing. Taking to Twitter shortly after Maria wrote: ‘Hello Melbourne.'I'm so happy to be back, you make our experience so much better