Home favourite Anke Huber upset fourth-seeded Kim Clijsters of Belgium 6-3 4-6 6-3 in the second round of the Filderstadt Grand Prix on Thursday.

The 26-year-old German, who has announced that she plans to retire at the end of the season, was given a standing ovation by the Filderstadt crowd after overcoming the French Open finalist.

Huber went on the offensive in the first set, catching Clijsters off guard with her belligerent game.

"I knew that I could play fast balls on this fast surface," Huber said, adding that she felt confident she could win the tournament for the third time and add the Porsche sports car prize to her collection.

"But I'm still a long way away from that," the 1991 and 1994 winner cautioned.

Huber will face Justine Henin in the quarter-finals after the Belgian beat Chanda Rubin of the United States 7-5 3-6 6-3.