Maria Sharapova [Images] looked back to her best as she overwhelmed Ana Ivanovic 6-1, 6-2 in her final round-robin match at the WTA Championships to set up a semi-final showdown with Russian compatriot Anna Chakvetadze [Images].

Defeat for Ivanovic means she has the daunting task of taking on defending champion and world number one Justine Henin [Images] in Saturday's other semi-final.

"I played really solid from the beginning," said Sharapova. "I gave it my all even though we both knew we'd already made it to the semis. I really wanted to win this match."

Sharapova has struggled with fitness problems this season and was unable to defend her Zurich and Linz titles because of a shoulder injury but she has looked sharp in Madrid this week.

The 20-year-old Russian, who only qualified for the prestigious $3 million event after Venus Williams withdrew because of health problems, started with a bang against a nervous-looking Ivanovic, breaking twice as she powered into a 4-0 lead.

The Serb broke her duck in the fifth game, but the former number one kept her opponent on the rack with some booming serves and deep returns to claim the set with ease.

Sharapova, who won the Championships on her debut appearance in 2004, showed no signs of relaxing in the second set.

She stretched the world number four around the court as she hit the lines with a succession of pin-point ground strokes, broke in the fourth and again in the eighth, clinching victory with a stunning passing shot.

Earlier world number three Jelena Jankovic was forced to retire from her final round-robin because of ill health while trailing 6-1 1-0 against Wimbledon finalist Marion Bartoli.

GRUELLING YEAR

"I've been sick for a couple of days and I'm having so much trouble breathing, I'm just suffering on the court and I can't play my game," said the 22-year-old who has endured a gruelling year in which she compiled 72 victories from 97 matches.

The retirement brought a premature end to a disappointing tournament for both players.

Jankovic went home without a win after losing to Henin and Chakvetadze in her previous matches, while Bartoli was deprived of a proper victory having been called in as a late replacement for the injured Serena Williams [Images].

The Frenchwoman was demolished 6-0 6-0 by Henin in her opening match on Thursday just hours after being told she would have to step into the tournament.

"It has been a very strange week for me," said Bartoli. "I heard at 1.15 in the morning that I would have to play the world number one Justine Henin and yesterday I got beat really badly.

"So my wish was to have fun and play a little better in the last match of the year and I'm really sorry for Jelena that it ending up like that."

Slovakia's Daniela Hantuchova [Images] beat world number two Svetlana Kuznetsova 7-6, 6-0 in a consolation match between the two eliminated players in Friday's late match.

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