MELBOURNE, (Reuters) – Kim Clijsters’s fairytale return to grand slam tennis came to a shuddering halt at the Australian Open yesterday just as Justine Henin’s own comeback started to gather momentum.

Clijsters was dumped from the first grand slam of the year after losing 0-6 1-6 to Russia’s Nadia Petrova. The result was shocking enough but the scoreline defied all expectations,  coming just four months after the Belgian won the U.S. Open.

Statistics can sometimes be misleading but the numbers in  this match accurately summed up the thrashing. Clijsters won just five points in the first set and 17 in total. It was all over in 52 minutes.

“She was good but I made all the mistakes and she didn’t  have to do that much. It just sucks it has to happen at this stage of this tournament,” Clijsters told reporters.

“This is something probably you want to forget as soon as  possible and go home.”

No one was more surprised by Clijsters’s meek performance  than Petrova. “I was preparing myself for a long day and a long  match,” she said. “It might have been a three setter.”

Clijsters’s loss overshadowed a special milestone by her  compatriot and long-time rival Henin, who beat Russia’s Alisa  Kleybanova 3-6 6-4 6-2, marking her 500th career win.

Henin would have reached her landmark a lot earlier if she had not decided to suddenly quit the sport in 2008 when she was the number one player in the world.

“It’s a big challenge to come back and I think I love  challenges. That’s the way I am,” Henin said.

“I need always to push myself and to push the limits back.  I’m very proud of what I’m doing right now.”

Juan Martin del Potro, Andy Murray and Andy Roddick all won  their matches with comparative ease but Rafa Nadal needed three  and a half hours to beat dogged German Philipp Kohlschreiber.

The defending champion eventually won 6-4 6-2 2-6 7-5 and  meets Croatia’s Ivo Karlovic in the fourth round.

“The most important thing is I won, so I’m happy about that but I am less happy about my game,” the Spaniard said. “But, you  know, everybody has not very good days.”

U.S. Open champion Del Potro showed no lingering effects of his five-set second round win over James Blake during his 6-3 0-6 6-4 7-5 win over German Florian Mayer.

Roddick recovered from a set down to defeat Spain’s  Feliciano Lopez 6-7 6-4 6-4 7-6. The American will next play Fernando Gonzalez of Chile after the 2007 Australian Open  runner-up outlasted Evgeny Korolev 6-7 6-3 1-6 6-3 6-4.

Murray overcame a minor injury scare and more questions  about his serve to beat Florent Serra of France 7-5 6-1 6-4 and is the only man through to the round of 16 who has not dropped a set.

“I don’t think my serve is an issue at all,” the Scotsman  said. “Everyone is panicking about my serve.”

Murray’s next opponent is John Isner, the 2.06 metre  American, whose main weapon is not hard to guess.

He thumped 26 aces past Gael Monfils in his 6-1 4-6 7-6 7-6  win over the Frenchman to lift his total for the championship to  81.

Dinara  Safina defeated Britain’s Elena Baltacha 6-1 6-2 in less  than an hour while Maria  Kirilenko matched her best performance at a grand slam when  she defeated Italy’s Roberta Vinci 7-5 7-6.

French Open champion Svetlana Kuznetsova needed all her big  match experience to dig herself out of trouble and beat German  qualifier Angelique Kerber 3-6 7-5 6-4.