Andy Murray says he is dismayed at Novak Djokovic's struggle to gain entry to Australia, saying it is "really not good for tennis at all".
The world number one is currently in an immigration detention centre.
"I think everyone is shocked by it," said Murray, who will also play at the tournament, which starts on 17 January.
"I'm going to say two things on it just now. The first thing is that I hope that Novak is OK. I know him well, and I've always had a good relationship with him and I hope that he's OK.