Former world number one Kim Clijsters [Images] will come out of retirement to play on the tour during the US hardcourt season later this year, the Belgian said on Thursday.

"I have missed playing tournaments most. I am doing it for the challenge. I have been training for 11 or 12 weeks. Training harder than ever before. Then this drive came back," Clijsters told a news conference at her home town of Bree.

The 25-year-old retired in May 2007 before marrying basketball player Brian Lynch and giving birth to a daughter. She has been training in at the tennis centre in Bree, north of Brussels in recent weeks.

"I have asked for wildcards for Cincinnati, Toronto and US Open [Images], that's all for the moment. I want to see if I can still do it," the 2005 US Open champion said.

According to her plans, Clijsters will make her comeback in the Cincinnati Open which begins on August 10 and continue her build-up for Flushing Meadows the following week in the Toronto Cup.

US Open organisers have already said they would grant her a wildcard for the final Grand Slam of the season.

She announced last week that she would compete in the World Team Tennis event in the United States and would also take part in a special event at Wimbledon [Images] in May, alongside Steffi Graf [Images], Andre Agassi [Images] and Tim Henman.

NEW CHALLENGE

"When I started preparing for the Wimbledon game with Steffi Graf I felt this drive. I wanted a new challenge. This is just for fun for now to see if I can do it," added Clijsters.

"I don't need to be number one again. I have done that and I don't need to do it again. I am just going to see how things evolve."

Clijsters won 34 singles titles and held the top ranking for a total of 19 weeks.

She had been plagued by injuries before she retired and on Thursday the Belgian said she is trying to make sure her second stint as a professional is not blighted by the same problems.

"I train six days a week, half of which is building up stamina and physique. I am really looking at [my] weak points to prevent injuries," she said.

"I am more mature now. You know how your body will react to certain things."

Despite her two-year absence from the tour, the popular Clijsters hopes she still has the game to compete at the highest level.

"I don't think there has been a huge change in the game for the past two years," she said.

Asked if she would play a full schedule if her comeback is successful, she added: "I'm not going to have the same type of schedule, 20, 21 tournaments. I want to see where I am and what is possible, how many weeks I can be away, those are the type of details I need to work out.

"It is very hard for me to say these are my long term plans. What I want is also influenced by my daughter and other family things.

"The comeback could of course fail but as long as I work hard I won't blame myself for anything... it is too early to say whether I will be returning for one, two or three years."

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