Top seed Henin defeated Russia's Olga Poutchkova 6-1, 7-5 on Rod Laver Arena.

It took The Belgian only 22 minutes to seal the first set but the Russian challenger broke Henin at 1-1 and 5-3 in the second set.

Henin fought her way back to break at 6-5 for the match.

"I played a good first set, well into the match and played very aggressive and I did a good job in the first," said Henin.

"Then I lost a little bit of the intensity, a little bit of the rhythm on my serve," she said.

"When she came back came back at 5-all, I understood it was time to push myself a little bit more," she added.

Nadal made few mistakes when the Spanish second seed stormed past Frenchman Florent Serra 6-0, 6-2, 6-2 in just 94 minutes.

He produced 39 winners and hit nine aces to book a third round position.

The 22-year-old was happy with his performance, better than last round.

"I played much better and I started very good. Maybe the opponent was a little bit easier, so I can come to the match. I can feel better the ball, " he said.

Nadal tried hard to fend off a strong challenge from Serbian qualifier Viktor Troicki, overcoming him 7-6 (7-3), 7-5, 6-1 in over two and a half hours on Monday.

He will next face French 28th seed Gilles Simon.

Unheralded Australian Casey Dellacqua stunned 15th seed Patty Schnyder of Switzerland 4-6, 7-5, 8-6 to set up a third round clash with 2006 Australian Open women's singles champion Amelie Mauresmo, who overcame Russian Yaroslava Shvedova 6-4, 7-6 (7-5).