Doubtful Rafa Nadal rules out Australian Open glory

Melbourne: Rafa Nadal has downplayed his chances of winning the Australian Open, saying his back remains a concern and he lacks confidence from having little match practice in the lead-up.

On the comeback trail after injury and illness wiped out the latter half of his 2014 season, the Spaniard had a poor start to his new year, dumped from the first round of the Qatar Open by German journeyman Michael Berrer.

"No, I don't consider myself one of the favourites here," the 28-year-old, seeded third for the tournament, told reporters at Melbourne Park.

"Last year, yes. This year is a different story. (I) would be lying if I say I feel that I am ready to win today. I don't feel myself ready to win the tournament here today.

"If I am here in a press conference in one week, maybe I will say another thing because I will have the feeling that I will play a few matches, and if I'm able to win that couple of matches, then probably I will have little bit more rhythm, I will have more confidence.

"But in theory, playing four, five matches in seven months, you cannot be a favourite of a tournament that is not clay, it's on hard (courts)."

Nadal made the final last year but was beaten by Stan Wawrinka in four sets, having carried a painful back injury into the match that affected his movement.

He recovered to win a record ninth French Open crown but was blighted by a wrist injury and then appendicitis late in the year.

"I cannot say (I am) completely recovered because that can happen when you compete, when you put your back under stress," Nadal said.

"It's something that I (am) not 100 percent confident yet.

"I am confident about my knees because (they) are working very well. But my back, I don't have enough time having good feelings to say I am 100 percent perfect, no?

"I need to take care about this for the moment. But hopefully it will be fine."

Nadal's fitness will be put to the test in a tough first round encounter against wily Russian veteran Mikhail Youzhny, a former top 10 player.

"It's true that having a grand slam that early in the season after injury like this is not the ideal thing.

"But here we are. I worked a lot since 10th of December.

"I am with calm and happy the way I did the things."