By Nick Mulvenney

MELBOURNE (Reuters) - Rafa Nadal opened his hotly anticipated Australian Open campaign with a ruthless dispatch of an ailing Brazilian journeyman on Tuesday, setting the tone for a day of pitifully one-sided contests at Melbourne Park.

Brazilian Marcos Daniel mustered up just 12 points in 46 minutes before he decided his injured left knee, and possibly his pride, could take no more and he called an end to the contest with Nadal leading 6-0 5-0.

The world number one knows very well the pain of injury having hobbled out of Melbourne Park in the quarter-finals when his own knees gave up on him last year, and he was full of sympathy for his 32-year-old opponent.

The short contest left Nadal, who was struggling with flu in the run up to the tournament, with little better idea of the level of his game.

"It's difficult to say I played really well or I played bad," he added. "I think I played right. I played some good shots, some long shots. The serve can be a little bit better. Yeah, that's the only point that I think I can improve."

U.S. Open champion Clijsters needed just 44 minutes to reach the second round, bustling around the court to clinically pick apart the hapless Russian.

"I do feel bad," Clijsters told reporters. "I even caught myself at 5-0 in the second set, she hit a couple of backhands down the line, I was like 'Yeah, that's it!'"

Safina, who according to the WTA became the first former women's number one to lose 6-0 6-0 at a grand slam since the rankings system began in 1975, was nonplussed by her form.

It took David Nalbandian 244 minutes longer than Clijsters to reach the second round, the Argentine outlasting her former boyfriend Lleyton Hewitt 3-6 6-4 3-6 7-6 9-7 in a four-hour 48-minute battle of attrition that finished at 1.07am local time.


Like Nadal, Andy Murray's passage was eased by a retirement when Slovakia's Karol Beck quit with the fifth seed 6-3 6-1 4-2 up, but the Briton's day was overshadowed by a freak incident involving his doubles playing brother Jamie.

"He hit a baby sparrow when he was practising his serve," Murray, the losing finalist here last year, said. "I think he killed it. My mum told me about it when I woke up this morning.

"I hope he didn't do it on purpose. I haven't seen him yet today. It was a pretty traumatic start to the day..."

"I'm not fearing anyone, but at the same time I fear all," said the Swede, who has never been past the second round at Melbourne Park.

"I know that when I play well, I can beat everyone. But the same time, I really have to play well because last year... I didn't play well at all and I lost first round."

Vera Zvonareva, the number two women's seed, rattled off a 6-2 6-1 victory over Austria's Sybille Bammer in the opening match on a cool and blustery Rod Laver Arena.

In the absence of injured 2010 champion Serena Williams, Australian hopes are high that Sam Stosur can break a three-decade drought without a local champion.

The fifth seed could not have done much better on Tuesday than her 6-1 6-1 drubbing of American wildcard and grand slam debutant Lauren Davis in another mismatch on center court.

"I think at the end of the day you've got to just take it for what it was," said a matter-of-fact Stosur. "I can walk off the court saying I hit the ball well, felt good, and moved well.

That's the day it was."

(Editing by John O'Brien and Pritha Sarkar)