Graeme Agars: Can Novak Djokovic win Grand Slam number 25? Previewing Australian tennis Open

Longtime tennis journalist Graeme Agars joins Martin Devlin on It's Only Sport, to offer a comprehensive preview of the Australian tennis Open underway in Melbourne. A number of first round matches have already been completed with defending men's and women's singles champions - Novak Djokovic and Aryna Sabalenka - both advancing to the second round. Graeme discusses how much longer Djokovic can perform at such a high level, who his closest rival is, and more.