Roger Federer pleased to overcome "tough" match

Roger Federer has expressed his delight in reaching the fourth round of the Australian Open.

The former world number one didn't drop a set against Ivo Karlovic but the Swiss pro slightly edged the match to clinch the win in Melbourne.

"Obviously there was not much baseline tennis out there," said Federer. "That's why it's hard to judge where my game is at, but I was in control. It was a good day at the office.

"I thought it was going to be at least one tie-break if not two, so one is good," said Federer. He's a tough man to play against. I am happy I found a way today and I am happy to be through."

Federer will face Bernard Tomic in the fourth round after the Australian defeated Alexandr Dolgopolov in five sets.