Andy Murray has admitted that he did not expect to win this year's Australian Open considering he had not long undergone back surgery.

Roger Federer defeated the British number one 6-3 6-4 6-7(6) 6-3 in the quarter-finals of the competition, and Murray concedes that he is not yet back to his best.

"I wasn't expecting to come in and win the event; that would have been completely stupid to think that," he told BBC Sport.

"It's a very tough thing to do playing against Roger at that level, and even if I'd won I would have had to play Rafa [Nadal] in a couple of days.

"I'm happy to be playing at a good level just now and, with a few more matches and a bit of training and working on a few things, I'll hopefully be back to my best at some stage this year."

Murray, who went under the knife in September, has only featured in one other tournament since his operation.