World number one Caroline Wozniacki believes parallels can be drawn between the mental approach required in tennis and golf having observed boyfriend Rory McIlroy at close quarters.

Victoria Azarenka led a quintet of leading players in cruising into the second round of the Australian Open today.

Laura Robson and James Ward both progressed through the final round of Australian Open qualifying in Melbourne but fellow Brit Naomi Broady fell in the second round.

It could be the mother of all Olympic comebacks. When Tia Hellebaut announced she was pregnant in December 2008 – four months after her historic victory in the women's high jump final at the Beijing Olympics – she said she had fulfilled everything she had ever wanted to in track and field and would be hanging up her spikes to concentrate on motherhood.

Petra Kvitova's memorable year ended in perfect fashion here yesterday when the 21-year-old Czech won the TEB BNP Paribas WTA Championships in her first appearance at the season-ending event. Kvitova's 7-5 4-6 6-3 victory over Victoria Azarenka in the final gave the Wimbledon champion her sixth title of the year and ensured that she would rise to No 2 in today's updated world rankings list.

Kim Jong-il called on the United States to end its "aggression" towards North Korea, in a rare interview published yesterday. North Korea's reclusive leader also told Itar Tass, the Russian state-owned news agency, that his country was ready to restart talks on the North's nuclear programme, in what the agency said was the eccentric dictator's first interview in nine years.

Serena Williams is ranked No 27 in the world, lost in the fourth round of the only Grand Slam event she has played in the last year and pulled out of her last tournament before the US Open with a toe injury. If the fact that the 29-year-old American is the overwhelming favourite to win the title here says much about the vacuum at the top of the women's game it is also a reflection of her extraordinary ability to come back from adversity.

Two-time defending champion Kim Clijsters has withdrawn from the US Open after failing to recover from a stomach muscle injury.

Kim Clijsters could miss out on the chance to defend her US Open title later this month after retiring against Zheng Jie at the Rogers Cup in Toronto. The Belgian was a set up when she withdrew with a stomach problem.

Women's second seed Kim Clijsters has withdrawn from Wimbledon due to a foot injury, tournament organisers announced today.

Lleyton Hewitt and Kim Clijsters, who were once engaged, are both rated doubtful to play at Wimbledon next week after aggravating long-standing injuries yesterday.

The men's and women's competitions here at the French Open have been a marked contrast. While the world's top four men were still in the competition going into yesterday's semi-finals, their female counterparts had departed before the same stage, some as early as last week.

Li Na's second chance to become the first Asian to clinch a singles grand slam title on Saturday has stirred patriotic fervour among home fans hoping to celebrate another milestone in China's rise in the sporting world.