Petrova shuts Kuznetsova out

Tennis: Australian Open: Croatian Cilic sends US Open champ Del Potro packing; Safina pulls out

Dinara Safina suffered the most. The Russian had to quit her fourth round match against Maria Kirilenko after her injured back flared up again, raising doubts about her immediate playing future.

"It's really, really terrible," she explained. "I cannot make any movement. Whatever I try to move, it hurts terribly."

Fatigue contributed to the surprise defeats of Argentina's US Open champion Juan Martin Del Potro and Svetlana Kuznetsova, the French Open champion. Both were able to finish their matches but their legs were heavy and their bodies weary.

"I will go home and I will see the doctors there," Del Potro said after his 5-7, 6-4, 7-5, 5-7, 6-3 loss to Croatia's Marin Cilic, an underrated player ranked 14th in the world.

Kuznetsova was beaten 6-3, 3-6, 6-1 by her fellow-Russian Nadia Petrova. She is the only seeded player left in the bottom half of the women's draw but plays Justine Henin in the next round after the former world number one beat her fellow-Belgian Yanina Wickmayer 7-6, 1-6, 6-3.

Killer instinct
Henin is playing just her second tournament since coming out of retirement. She has retained the same killer instinct that enabled her to win seven grand slam titles but is concerned about the effects on her health.

Rafael Nadal and Andy Murray brought down a pair of giants to set up a tantalising quarter-final between two of the biggest names in men's tennis.

Nadal defeated Ivo Karlovic, a 2.08 metres tall Croatian whose serves come down like thunderbolts 6-4, 4-6, 6-4, 6-4, while Murray beat the 2.06 metres American John Isner 7-6, 6-3, 6-2.

Nadal’s match against Karlovic was not one for the traditionalists, more like pistols at dawn than the genteel game once played at Victorian garden parties.

Karlovic rifled 28 aces past the Spaniard but the defending champion knows a thing or two about how to win.

The world number two remained patient, rolled the dice a few times and correctly guessed which way to go, then took his chances when they came.
Kirilenko’s joy at reaching her first Grand Slam quarterfinal was tempered by her concern for her Russian compatriot.

Kirilanko's next opponent is China's Zheng Jie, who defeated Ukraine's Alona Bondarenko 7-6, 6-4 while Cilic will face Andy Roddick after the American wore down Chile's Fernando Gonzalez 6-3, 3-6, 4-6, 7-5, 6-2 in a fiery late-night encounter.

Fourth-round results at the Australian Open on Sunday (prefix denotes seeding):
Men’s singles: 7-Andy Roddick (US) bt 11-Fernando Gonzalez (Chi) 6-3, 3-6, 4-6, 7-5, 6-2; 14-Marin Cilic (Cro) bt 4-Juan Martin Del Potro (Arg) 5-7, 6-4, 7-5, 5-7, 6-3; 2-Rafael Nadal (Spa) bt Ivo Karlovic (Cro) 6-4, 4-6, 6-4, 6-4; 5-Andy Murray (Bri) bt 33-John Isner (US) 7-6 (7-4), 6-3, 6-2.

Women’s singles: Maria Kirilenko (Rus) bt 2-Dinara Safina (Rus) 5-4 (retd); Justine Henin (Bel) bt Yanina Wickmayer (Bel) 7-6 (7-3), 1-6, 6-3; 19-Nadia Petrova (Rus) bt 3-Svetlana Kuznetsova (Rus) 6-3, 3-6, 6-1; Zheng Jie (Chn) bt 31-Alona Bondarenko (Ukr) 7-6 (7-5), 6-4.