[2] Following her loss to Marion Bartoli in the Wimbledon semifinals she went undefeated for the rest of the year, in the process becoming the first woman to earn over $5 million in a single season.

Kim Clijsters cut her farewell tour short by retiring abruptly in May, having originally been due to play her last event in October.

Serena Williams started the season by unexpectedly winning her eighth singles Grand Slam title at the Australian Open.

Williams won the title in emphatic fashion, thrashing Maria Sharapova in the final in a performance that BBC Sport called "arguably the most powerful display ever seen in women's tennis.

Defending champion Amélie Mauresmo suffered an early loss to Lucie Šafářová, allowing Nicole Vaidišová to reach her second Grand Slam semifinal.

Kim Clijsters bade a tearful farewell to her home crowd in Belgium, playing Antwerp for the final time due to her planned retirement in October.

Elsewhere Serena Williams backed up her Australian Open triumph with a win in Miami, saving match points against Henin in the final.

Serbians Jelena Janković and Ana Ivanovic dominated the clay season leading up to the French Open, winning the three biggest warm-up tournaments.

Also during the clay court season Kim Clijsters announced her retirement, months earlier than anticipated, following an early loss in Warsaw.

Other upsets included Vaidišová's win over the defending champion Mauresmo, who continued to struggle for form throughout the season aside from a run to the final in Eastbourne.

On the summer hardcourts Anna Chakvetadze produced some strong results, winning back-to-back titles in Cincinnati and Stanford, and then reaching the semifinals in San Diego, being stopped by eventual champion Sharapova.

Chakvetadze backed up her successful results in the warm-ups by reaching her first Grand Slam semifinal, advancing from a quarter that saw defending champion Sharapova knocked out by Agnieszka Radwańska in the third round.