Roger Federer has admitted that he was required to produce a high-quality performance to see off the challenge of Simone Bolelli in the Australian Open second round.

The second seed dropped the first set against the world number 48 before winning in four sets, and the Swiss, who has won the tournament in Melbourne on four occasions, revealed that he didn't start to play freely until the latter stages of the contest.

After the match, the 33-year-old told reporters: "It was a great match. I thought Simone played really, really well in the first set. I wasn't playing badly, but I really had to fight until the middle of the third set.

"Once I got the break, I was able to relax a little bit and I maybe played a bit better because there was less pressure. It was tough but I'm really pleased to come through."

Federer will play either Jeremy Chardy or Andreas Seppi in the last 32 on Friday.