A LITTLE punch of the air, a big smile and Roger Federer was back.

Six months after injuring his knee at Wimbledon, the 17-times Grand Slam champion made a winning return to the court, beating Juergen Melzer of Austria 7-5, 3-6, 6-2, 6-2 to reach the second round of the Australian Open.

There might even have been a touch of nerves from Federer, especially in the early stages, as he was broken 4-2 by fellow 35-year-old Melzer.

But the former world No 1, seeded 17 this year, hit back to take the set and, when he led 3-1 in the second, it looked like he would be off in a hurry. However, Melzer played some stunning tennis to win five straight games and level the match.

Federer, who was given a rapturous reception by the crowd, stepped up a level in the third and fourth sets, though, to seal a second-round meeting with American Noah Rubin.

“It is good to be back,” Federer said. “Even if I’d lost, it would have been good because I am on the court. It’s been a long road back but now, hopefully, I’ll stick around for a while.”

Meanwhile, Federer may not think Nick Kyrgios can win the title this year – “can he win back to back to back to back against four or five top players? I don’t think so,” he said – but the Australian made a superb start to his campaign.

Kyrgios was at his dynamic best as he crushed Gastao Elias of Portugal, despite his sore knee, and said he was keen not to waste any energy.

“In general, if you happen to go deep, it gets pretty tiring,” he said. “So you just want to reserve that mental energy and other parts of your body as well. The quicker you can get it done, the better it is for deeper in the week.

The 21-year-old, who is seeded 13th, now plays Italy’s Andreas Seppi while the Swiss No.1, Stan Wawrinka, recovered from a break down in the fifth to beat Martin Klizan of Slovakia.

Kyrgios refused to respond to Federer’s words, but said he was confident in his ability.

“If I didn’t think I’d win it, why would I play?” he said. “I think I can win it. I’ve beaten pretty much everyone in the draw before. So I think so.”

Defending women’s champion Angelique Kerber dropped a set but recovered to beat Lesia Tsurenko of Ukraine 6-2, 5-7, 6-2 but fourth seed Simona Halep, carrying a knee issue, was dumped out 6-3, 6-1 by American Shelby Rogers.

“I think it’s always good to have a match like this in the first few rounds,” said top seed Kerber.

“It’s always tough for everybody to get the rhythm in the first grand slam of the year.”