Melbourne - Caroline Wozniacki said on Saturday that she has no regrets and it is "the right time" to walk away from tennis with the former No 1 set to retire after the Australian Open.

But the Dane, whose only Grand Slam triumph came in Melbourne in 2018, admitted that she will be "a bit emotional" when the moment finally comes over the next fortnight.

Wozniacki announced in December that she would retire from tennis to focus on other things, including starting a family with husband and former NBA star David Lee.

"There's been a lot of thoughts. It's (retirement) been something I've been thinking about for a long time, for a while," the 29-year-old, now ranked 35 in the world, told media in Melbourne.

"I just looked at my life, at my career, everything else, and I just had a look inside of myself and it felt right. It felt like the right time for many reasons."

Wozniacki was diagnosed with rheumatoid arthritis in 2018 but says that has nothing to do with her decision to quit after the Australian Open, which begins on Monday.

The Dane, who begins her final tournament against Kristie Ahn of the United States, added: "I've achieved a lot, I've given it my all.

"Every single day I go out and I work so hard to stay at the top or to get back to the top, whatever it may be.

"It doesn't feel the same. I still want to work hard, but I want to do something different."

"Honestly, I'm leaving with no regrets at all because I've worked so hard my whole life, my whole career," Wozniacki added.

Wozniacki, who finished 2010 and 2011 on top of the rankings but had to wait until 2018 to finally win a Major, does not anticipate emulating Kim Clijsters, the former number one who is set to return to tennis seven years after retiring.

The 36-year-old Belgian will not be at the Australian Open, having delayed her comeback because of injury, and Wozniacki warned that returning after so long out will be tough.

"I personally don't think so," Wozniacki said, asked if she expects Clijsters to challenge once more for Grand Slams.

"She can prove me wrong.

"I think tennis has changed in seven years. I don't think it's as easy - I don't know if she thinks it's easy - I know it's not as easy as it looks from the outside."

Wozniacki played doubles with close friend Serena Williams last week at the Auckland Open, where they were beaten in the final.

"It's probably the most fun I've had on court, we had a blast," she said.

"We would pretend to talk tactics - we really would talk about everything else," Wozniacki added, laughing.

"Just went out there and had fun, enjoyed ourselves.

"I'm so happy that I got to play with her before my career was done."