Melbourne : Defending champion Rafa Nadal has declared himself fighting fit for the rigours of a grand slam but the world number two is not certain he will be back to his best at the Australian Open tomorrow.

Nadal, whose five-set defeat of Roger Federer in last year's final left the Swiss maestro in tears, has struggled to reach his all-conquering best since knee tendonitis forced him off the tour for two months after the French Open.

"I think I'm playing much better than what I did the last four months," the six-time grand slam champion told reporters.

"I'm ready to try to play my best tennis, I think. I don't know here."

Since returning to the tour at the Montreal Masters in August, Nadal has not won an ATP title and has looked short of his fist-pumping best, although he reached the semifinal of the US Open where he was beaten by winner Juan Martin del Potro.

After crashing out with three successive losses at the ATP Tour Finals in London, Nadal said he needed time out to recharge his batteries and find some confidence.

He helped Spain to a Davis Cup victory over Czech Republic in Barcelona in December and has warmed up for the Australian Open with a win at an exhibition tournament in Abu Dhabi and reached the final at the Qatar Open where he lost to Nikolay Davydenko.

"The only way to have confidence is winning matches, and winning important matches," Nadal said.

"So I did that in Abu Dhabi, I did that in Doha. So I think now I'm really in the right way."

Plunging back

The Spaniard has drawn 78th-ranked Peter Luczak of Australia in the first round and could face Briton Andy Murray in the quarterfinals.

Nadal, who allowed himself scarcely a day's break after the Davis Cup ended on December 6 before plunging back into training, said there were no question marks over the strength of his knees.

He also shrugged off not having outright favourite status, saying that people had been telling him he was favourite at the French Open every year before his 31-match reign was broken by Swede Robin Soderling.

"On hard court there's a lot of very good players and think being number two of the world, probably I am not the ... favourite but I am one of these ones, you know.

"Finally, the important thing is who plays better on court ... We will see what happens next week."