Melbourne - A disbelieving Kim Clijsters was at a loss to explain her humiliating defeat to Russia's Nadia Petrova in the third round of the Australian Open on Friday.
The 19th seeded Petrova stunned Clijsters when she demolished the reigning US Open champion 6-0, 6-1 in just 52 minutes.
The Belgian was a shadow of her normal self as Petrova totally dominated a one-sided match to the dismay of most fans at Melbourne Park's Hisense Arena, and Clijsters herself.
"You don't want this to happen during a match, especially at a Grand Slam," Clijsters said.
"I felt like I had a really good preparation, so that's the thing, everything had been going pretty good up until today."
Clijsters said she had not changed any of her preparation and felt like nothing was amiss during her warm-up on court.
"I'm very superstitious with my routines and everything, so I really stick to that every day," she said.
"I ate the same, slept the same, everything -- that's why it's even more confusing in a way, as well."
From the moment this year's Australian Open began, all the talk has been about the return to Grand Slam tennis of Clijsters and countrywoman Justine Henin.
But while Henin scraped through against Russia's Alisa Kleybanova earlier in the day, Clijsters was blown off court by the powerful Russian, who scored her first win over the Belgian in five meetings.
"I really tried to focus on winning every single point," Petrova said, adding that she had been preparing for a long three-setter.
"(But) when I broke her again in the second set, then I realised, you know, this is like a two-set match for me, and I just started cruising through it.
"I played very well -- I didn't give her a chance to start playing her game," Petrova added
"I really put pressure on from the first point. Also, I was coming up with the big shots. I made it very difficult for her."
Clijsters said she tried to turn things around but she could do nothing to stop the rot.
"I was just questioning myself, just questioning myself out there a lot," she said.
"You don't really know, why is this all of a sudden happening?
"You just try to stay calm because there were points where I really like wanted to break my racquet into pieces, but ... that's not going to help either.
"At some points I was just happy I was hitting a ball in -- that's how bad it was."
Petrova raced through the first set in only 18 minutes, with Clijsters winning a measly five points in the first six games.
The second set was not much better for the Belgian world number 15 as the 28-year-old Petrova ruthlessly took advantage of her opponent's struggles.
The loss was a sad end to the tournament for the much-loved Clijsters, who came back to tennis midway through last year after getting married and having a baby.
She capped her comeback with a sensational triumph at September's US Open, then added the Brisbane International to her trophy cabinet in the first week of 2010.
Petrova has now made the fourth round at the Australian Open for her third straight year, while it is Clijsters' earliest exit since she first played in Melbourne 10 years ago and lost in the first round.
"This is something probably you want to forget as soon as possible," Clijsters said.