Tennis legend Martina Navratilova was one of the main attractions at the Hong Kong International Art Fair's Wednesday night Vernissage - that's French for private viewing. Stationed just outside the main entrance, Navratilova (pictured) was whacking paint-dipped tennis balls onto a canvas. These days she's using her ferocious forehand for something other than Grand Slam championships. Collaborating with artist Juro Kralik (also in photo) since 2000, they make abstract art pieces that, I dunno, speak to man's existential search for life's meaning? 'This is something that I have never done before, working with Juro,' the tennis legend explained at a press conference on Tuesday. 'At first, I thought it was something strange but new to me, so I am into it.' Whatever it is, it looks like it was inspired by the tracking computer that shows whether balls are in or out during matches. The duo has four other works on display and on sale during the fair in aid of The Sovereign Art Foundation's arts rehabilitation and therapy programme for disadvantaged children. So far, they've produced about 300 paintings and might have created more - except Navratilova, 52, was still playing tournaments until a couple of years ago. 'In 2000, Martina had already retired and I thought she would have a lot of time to create the project together,' Kralik said. 'But then, in the same year, she returned to the court playing doubles. The problem was she was always winning and the more she won, the more tournaments she needed to play. Hence more travels and practice. In the end, I ended up taking the canvas and paint with me and followed her around the world.'