Clijsters feared a serious wrist injury would prevent her competing again at the top level, but she bounced back in style this year to win back-to-back titles at Indian Wells and Miami.
It was at Indian Wells last year when her wrist problems first began. A comeback attempt in Berlin ended in frustration and led to surgery shortly before Wimbledon.
Then when she was playing in a small tournament in Belgium in October she tore a tendon and feared the worst.
"They said it can heal in any normal person who doesn't have to use it in the position that I have to," said Clijsters in Warsaw where she is competing in her first European claycourt tournament of the season.
"But in my position (it could be) that it doesn't heal, and when I heard that I really didn't want to believe it."
It was then that she turned to her father, the Belgium footballer of the year in 1988, for advice.
"That's when my dad helped me. He's a very positive-minded person," she said. "He went through a lot of problems with his knees when he was playing soccer.
"He was in a similar situation where he had surgery and was out for eight months and people were writing him off after that.
"Then in his first training session he fell and his knee went again, and he was telling me that story and it gave me a lot of positive energy, that he could come back."
The 21-year-old Clijsters, currently ranked 17th in the WTA rankings, said there were moments when she began making plans for a life outside professional tennis.
"At the time when I was thinking what I could do if I couldn't play, there were things going through my mind that I'd like to do," she said.
"I've bought property and like to renovate. I decorated my house, just little things like that, to be busy.
"I love to work with kids. My sister has tennis camps in Belgium now and I was helping her with that. But not yet. There's time to do those when I'm older."
For now she is relishing being back in the sport she loves and believes it is an exciting time for women's tennis.
"I love the way tennis is at the moment," she said. "To be a part of it is great. There are so many different personalities and different games, and I like that they hit the ball hard. I enjoy playing against those girls."
Clijsters, seeded seventh in Warsaw after gaining a wildcard, plays Tatiana Perebiynis of the Ukraine in the opening round on Tuesday.