Rafael Nadal crushes Mikhail Youzhny in Melbourne

Nadal, beaten finalist against Stan Wawrinka last year, will next play either Australian Luke Saville or American Tim Smyczek.

Undercooked and on the comeback trail after a long lay-off due to injury and illness, the third-seeded Spaniard needed only a handful of games at Rod Laver Arena before clicking into grand slam gear.

Needing less than two hours to account for former top-10 player Youzhny, he prowled around the centre court like an uncaged tiger, blazing winners and pumping his fists in an emphatic return to Melbourne Park.

[DAY ONE ROUND-UP: Ivanovic falls as women's seeds tumble, but Aussie stars shine]

"Very positive result for me," the 28-year-old told reporters.

[DAY ONE ROUND-UP: Ivanovic, Kuznetsova and Lisicki all go out as seeds tumble]

"Always before the first match you always have the doubts, especially in this situation I'm arriving here.

"Every match is very important for me today. (It) was a comfortable victory that give me some confidence."

The year's first grand slam has doled out more heartbreak than glory for the 14-time major winner in recent years, and after missing the 2013 tournament with illness, he carried a back injury into last year's final and lost to Stan Wawrinka.

Having had encouraging runs at Melbourne Park cut short by injury flare-ups, Nadal was at pains to play down his Youzhny demolition as just one victory on a long road back.

He also showed a Zen-like resignation in the face of his many long-term injuries, which have forced him to re-boot his career three times after long lay-offs.

"At the end, you know that you not going to be at 100 percent, so the most important thing when you are coming back is accept all the challenges, the weeks, months, that you didn't have the chance to be able to practice, to compete," said Nadal, who faces American Tim Smyczek in the next round.

"Accept that you're going to be a little slow, a little out of rhythm. You can practise a lot. I did. I practised I think enough and with the right attitude, but at the end what you need is matches."

A famously fidgety player, Nadal's short-tugging antics between points have been a hallmark of his play, so it was with some curiosity that he appeared in a shorter pair at Rod Laver Arena.

"I feel more comfortable here, more fresh," he said. "Sometimes it's good to have some changes, to try different things. But seriously, I prefer this way."

Nick Kyrgios (Australia) beat Federico Delbonis (Argentina) 7-6(2) 3-6 6-3 6-7(5) 6-3

Thanasi Kokkinakis (Australia) beat 11-Ernests Gulbis (Latvia) 5-7 6-0 1-6 7-6(2) 8-6

Malek Jaziri (Tunisia) beat Mikhail Kukushkin (Kazakhstan) 6-2 6-3 2-6 7-6(3)

Simone Bolelli (Italy) beat Juan Monaco (Argentina) 6-3 3-6 6-3 6-1

2-Roger Federer (Switzerland) beat Lu Yen-Hsun (Taiwan) 6-4 6-2 7-5

23-Ivo Karlovic (Croatia) beat Ruben Bemelmans (Belgium) 6-4 6-2 6-4

Viktor Troicki (Serbia) beat Jiri Vesely (Czech Republic) 6-3 3-6 6-2 6-3

Dudi Sela (Israel) beat Jan-Lennard Struff (Germany) 6-4 4-6 3-6 6-3 7-5

Samuel Groth (Australia) beat Filip Krajinovic (Serbia) 6-3 7-6(4) 6-4

Jurgen Melzer (Austria) beat Victor Estrella (Dominican Republic) 6-1 6-4 6-2

28-Lukas Rosol (Czech Republic) beat Kenny De Schepper (France) 4-6 6-2 6-7(4) 6-3 6-4

22-Philipp Kohlschreiber (Germany) beat Paul-Henri Mathieu (France) 6-2 6-2 6-1

Bernard Tomic (Australia) beat Tobias Kamke (Germany) 7-5 6-7(1) 6-3 6-2

26-Leonardo Mayer (Argentina) beat John Millman (Australia) 6-3 6-3 6-2

Marcos Baghdatis (Cyprus) beat Teymuraz Gabashvili (Russia) 6-2 6-7(5) 3-6 6-4 6-4

Tim Smyczek (U.S.) beat Luke Saville (Australia) 7-6(2) 7-5 6-4

Edouard Roger-Vasselin (France) beat 15-Tommy Robredo (Spain) 2-3 (Robredo retired)

James Duckworth (Australia) beat Blaz Kavcic (Slovenia) 6-2 5-7 7-6(7) 3-6 6-2

3-Rafa Nadal (Spain) beat Mikhail Youzhny (Russia) 6-3 6-2 6-2

7-Tomas Berdych (Czech Republic) beat Alejandro Falla (Colombia) 6-3 7-6(1) 6-3

20-David Goffin (Belgium) beat Michael Russell (U.S.) 6-3 6-3 5-7 6-0

6-Andy Murray (Britain) beat Yuki Bhambri (India) 6-3 6-4 7-6(3)

24-Richard Gasquet (France) beat Carlos Berlocq (Argentina) 6-1 6-3 6-1

14-Kevin Anderson (South Africa) beat Diego Schwartzman (Argentina) 7-6(5) 7-5 5-7 6-4

Marinko Matosevic (Australia) beat Alexander Kudryavtsev (Russia) 6-4 6-7(5) 4-6 7-5 6-3

Lukas Lacko (Slovakia) beat Maximo Gonzalez (Argentina) 4-6 6-2 7-5 6-7(4) 6-1

Ricardas Berankis (Lithuania) beat Igor Sijsling (Netherlands) 2-6 6-4 7-6(2) 6-7(6) 6-4

Andreas Seppi (Italy) beat Denis Istomin (Uzbekistan) 5-7 6-3 2-6 6-1 6-4

29-Jeremy Chardy (France) beat Borna Coric (Croatia) 3-6 6-4 7-5 6-4

Joao Sousa (Portugal) beat Jordan Thompson (Australia) 6-4 7-6(5) 6-4

32-Martin Klizan (Slovakia) beat Tatsuma Ito (Japan) 7-6(6) 6-2 6-4

10-Grigor Dimitrov (Bulgaria) beat Dustin Brown (Germany) 6-2 6-3 6-2