Venus Williams hobbled while Wozniacki and Henin cantered on Wednesday but all three reached the third round of an Australian Open where upsets continue to be thin on the ground.

Williams, returning to action here for the first time since last year’s US Open, was severely hampered by what appeared to be a groin problem but still managed to scramble a 6-7 6-0 6-4 victory over world number 97 Sandra Zahlavova.

The seven-times grand slam winner took a medical timeout after losing the first set tiebreak and then gritted her teeth and summoned up her wealth of experience to grind out a victory in a shade over three hours.

“It was really tough,” Williams, flying the family flag alone this year in the absence of injured 2010 champion Serena. “But I’m a long way from home. It’s such a long way home and I didn’t want to go back yet.

“You’ve got to be able play in all circumstances — good, bad strange, weird, bizarre. I haven’t retired from a match in a long time. I have to go to the bitter end.”

Top women’s seed Wozniacki earlier looked in fine fettle as she took just 58 minutes to overpower American Vania King 6-1 6-0, continuing an impressive start to her attempt to vindicate her number one ranking with a first grand slam title.

Wozniacki’s win set up a third round opportunity to avenge her loss last week in Sydney to Slovakia’s Dominika Cibulova, who advanced with a 6-1 4-6 6-2 win over Italian Alberta Brianti.

“I definitely felt like I was playing good tennis today,” 20-year-old Wozniacki said, adding: “I believe that I’m a really good player, I can beat anyone on a good day.”

Henin was shaking hands with the umpire on Rod Laver Arena moments after Wozniacki clinched her win, having put Briton Elena Baltacha to the sword 6-1 6-3.

Seeded a lowly 11^th, Henin was still feeling the elbow injury that kept her out of the game for six months last year and said the unseasonably low temperatures had not helped.

Unhelpful Weather

“It’s the worst conditions actually,” said Henin, the 2004 champion at Melbourne Park. “The weather doesn’t help, that’s for sure. So I wasn’t feeling at my best on this part today.

“But I have to deal with it and get ready, be focused on your game, even if it’s not easy. But I did a good job about that.”

Twice grand slam winner Svetlana Kuznetsova of Russia, a 6-1 6-4 winner over Dutch qualifier Arantxa Rus, stands in Henin’s path to the fourth round.

France’s 15^th seed Marion Bartoli was beaten 3-6 6-3 6-0 by Vesna Manasieva of Russia but 2009 champion Maria Sharapova survived an early scare to rally to a 7-6 6-3 victory over Virginie Razzano in another Franco-Russian encounter. In the men’s draw, former world number five Tommy Robredo also registered something of an upset with a 1-6 6-3 6-3 6-3 victory over American 16^th seed Mardy Fish.

Robredo’s fellow Spaniard Fernando Verdasco faced an early exit but made a great escape by coming back from two sets down and saving a match point in the fourth set on his way to a 2-6 4-6 6-4 7-6 6-0 win over Serbian Janko Tipsarevic.

“I kept fighting all the time, because I was really close to losing today,” said the ninth seed. “I think that just my mentality was one of the biggest keys to my comeback today.”

Thomas Berdych also had to fight back after losing the first set to German Philipp Kohlschreiber but the sixth seeded Czech found his range and ran out a comfortable 4-6 6-2 6-3 6-4 winner.

Defending champion Roger Federer makes his second appearance of the tournament against Frenchman Gilles Simon in the evening session on Rod Laver Arena.