Rafael Nadal continued his ominous form at the Australian Open today as he made light of the sweltering conditions to sweep past Croatia's Roko Karanusic 6-2, 6-3, 6-2.

The world No1 took a cold shower before the second-round match and used ice to cool his head and neck to combat the Melbourne heat which went past 95°F today.

There was also stifling humidity but the Spaniard wasn't troubled as he needed just one hour and 37 minutes to beat the world No92.

The match lasted 20 minutes longer than Nadal's first-round demolition of Christophe Rochus and he has now given up just 11 games in the tournament so far.

Nadal has targeted the Australian and US Opens in a bid to complete the set of Grand Slam titles having already dominated in Paris and clinching the Wimbledon crown last year against his great rival Roger Federer.

He is confident of achieving that goal and is benefiting from the enforced six-week lay-off caused by his knee injury at the end of last year.

Nadal said: "When you win in Toronto and the Olympics on this kind of surface against the best players of the world, then why can't I win a Grand Slam on hard court?

"I am always trying to improve on this surface and, hopefully, this year I have a chance to win here and at the US Open."

Nadal now has a third-round encounter against Tommy Haas, who was the world No2 seven years ago but has since seen his career blighted by shoulder operations.

Although the German is now 79th in the rankings, the match should still provide the kind of quality contest the women's game does not generate this early in a Grand Slam.

"Tommy is going to be a very good test and I will have to play very well if I want to win," added Nadal.

Haas has lost all three previous matches against Nadal but is taking a positive attitude and believes his opponent is more vulnerable early in tournaments.

It may be wishful thinking on his behalf but Haas is still equipped to cause Nadal some discomfort, despite that dodgy shoulder.

Haas said: "Rafa needs to get his range and confidence and that's why I am looking forward to playing him at the third-round stage.

"I wouldn't want to play him at the same stage of the French Open on clay but I will aim to put him under pressure here.

"I am going to go for it and hope for the best and it's not like boxing where you can get at your opponent and the only way to hurt him is to hit some winners. I am playing the No1 player in the world and have nothing to lose and while my chances don't look very good on paper - given my previous results - I believe I have a shot."

Like Nadal, Haas had an easy win today, needing just over 90 minutes to beat Italy's Flavio Cipolla 6-1, 6-2, 6-1.

Sixth seed Gilles Simon, of France, defeated Australia's Chris Guccione 6-7, 6-4, 6-1, 6-2 while the 13th seed, Chile's Fernando Gonzalez, also looked in good form when beating Guillermo Canas, of Argentina, 7-5, 6-3, 6-4.

Meanwhile, Serena Williams moved into the third round with a 6-3, 7-5 victory over Argentina's Gisela Dulko and promptly gave herself a "D-minus" rating for her efforts.

The US Open champion is chasing a 10th Grand Slam title and a fourth Australian Open crown as the No2 seed and there is no doubting her wish to regain the No1 place currently held by Jelena Jankovic, of Serbia.

Williams was so annoyed by her form against Dulko that the American headed to the practise court to try and improve a power game that few in the sport can match.

She said: "My form was at like a D- minus at best. That's pretty far away. But it's good that I was able to win, too, when I wasn't playing my best. I definitely will try to do better."