FIFTH seed Ana Ivanovic admitted she was in need of a new approach after becoming the biggest casualty on day one of the Australian Open in Melbourne.
Ivanovic looked to be in charge of her match with Czech qualifier Lucie Hradecka on Rod Laver Arena when she took the first set 6-1, but won just five more games in a 6-1 3-6 2-6 defeat.
Maria Sharapova (right) and Eugenie Bouchard safely advanced to the second round, but ninth seed Angelique Kerber was one of eight seeds to make an early exit from the bottom half of the draw.
Ivanovic reached the last eight here last year and came into the event on the back of reaching the final of the recent WTA Tour event in Brisbane.
But the 27-year-old Serbian has now failed to reach a single Grand Slam semi-final in 27 attempts since winning the French Open in 2008.
"I think the whole match I didn't really feel like myself out there," the former world number one said. "It was really tough for me to find my rhythm.
"It's really disappointing. You know, it's probably the worst thing could happen. But still, the year is young and I really have to now sit and work on a few things and just maybe try to have a different approach to this kind of event and try to see what was lacking."
World number 142 Hradecka could hardly comprehend what she had achieved, adding: "I still don't believe that it's true. Probably in a couple of hours I will know that I am
in the second round in Australian Open and I beat Ana. It's two hours after the match and I'm still smiling."
Kerber was beaten 6-4 0-6 6-1 by Romania's IrinaCamelia Begu, while there were also defeats for Belinda Bencic, former US Open champion Svetlana Kuznetsova and 2013 Wimbledon finalist Sabine Lisicki.
Third seed Simona Halep lost the first two games of her match with Italy's Karin Knapp but bounced back to win 6-3 6-2, while second seed Sharapova beat Petra Martic 6-4 6-1 and Bouchard defeated Anna-Lena Friedsam 6-2 6-4.
Sharapova said she was well aware of the number of seeds being beaten and was determined not to become another casualty.
"I think especially from the media and the press side, you always talk about the match-ups, the draw, as in the future opponents," she said.
"Realistically it's important to focus on what's ahead you. You can't look further than your next opponent.
"There were quite a few upsets today. Of course I was very well aware of that. I watched some of it on TV. I had a long day before my match.
"I certainly didn't want to be one of them."