Clijsters prepares for emotional grand slam farewell at U.S. Open

But this year, the U.S. Open will serve as the swansong to Kim Clijsters' rollercoaster career, and the popular Belgian is aiming to bow out with a fourth Flushing Meadows crown.

"(I am) too old to play the game that I want to play physically," the 29-year-old, who initially retired from the sport to give birth to her first child in 2007, told the New York tournament's official website.

"I've put my body through enough strain and everything. The whole lifestyle, that's what I'm dealing with now, the lifestyle I've had for the last 15, 20 years."

The former world No. 1 turned pro in 1997 and has won 41 WTA Tour titles in addition to her three U.S. Open triumphs and her 2011 success at the Australian Open.

"I think for me the most important thing is I've always followed my heart," she continued. "I've always done what I felt was right. I've always stayed true to who I am.

"Players change. There's so many other things involved than just tennis and practicing. I think you see players kind of losing the true sense of life, and of the sport."

Clijsters took the sport by storm on her return in 2009, winning the U.S. Open as a wildcard to become the first mother to take a grand slam title since Australia's Evonne Goolagong Cawley in 1980.

She successfully defended her title 12 months on, before adding the Australian Open to her collection just five months later, beating China's Li Na in the final, CNN reports.

"I didn't expect obviously when I started back after having Jada, I never expected that things would be going so well so soon," she added. "It's been an incredible adventure these last three, four years.

"I feel like I've been able to kind of finish that chapter of my tennis year on a good note."

Clijsters returned to the top of the world rankings in February last year, but her body began to let her down.

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