Justine Henin-Hardenne defeated compatriot and rival Kim Clijsters in the final, 6–3, 4–6, 6–3 to win the women's singles tennis title at the 2004 Australian Open. It was Henin-Hardenne's third Grand Slam title, and her third win against Clijsters in a Grand Slam tournament final, after her victory at the 2003 French Open and the 2003 US Open. Clijsters would go on to win the title seven years later.
Justine Henin-Hardenne defeated her rival Kim Clijsters in the final, 7–5, 6–1 to win the women's singles tennis title at the 2003 US Open. She lost only one set during the tournament. Clijsters' loss in the final was her last defeat at the US Open until 2012, as she would go on to win her next 22 US Open matches, including three titles in 2005, 2009 and 2010.
Venus Williams was the defending champion, but chose not to participate that year.
The women's singles of the 2009 ECM Prague Open tournament was played on clay in Prague, Czech Republic.
Pauline Parmentier was the defending champion, but she was defeated in the second round by Magdaléna Rybáriková.
Defending champion Serena Williams successfully defended her title, defeating Justine Henin in the final, 6–4, 3–6, 6–2 to win the women's singles title at the 2010 Australian Open. It was her fifth Australian Open singles title and twelfth major singles title overall, surpassing the Open Era record for the most Australian Open singles titles. This was Henin's first major since the 2008 Australian Open, following her retirement in May 2008. Henin was unseeded at a major for the first time since the 2001 Australian Open and was awarded a wild card into the tournament.
Kim Clijsters won her first Australian Open title and her fourth Grand Slam overall by beating Li Na 3–6, 6–3, 6–3 in the final to capture the women's singles tennis title at the 2011 Australian Open. Li became the first Asian player to make the final of a Grand Slam in singles. Though she lost in the final, she would go on to win the French Open a few months later. Serena Williams was the two-time defending champion, but a foot injury during the middle of the 2010 season prevented her defending the title.
Kim Clijsters was the defending champion, but withdrew before her third round match against Laura Granville due to a wrist injury which would ultimately sideline her for the remainder of the season.
Kim Clijsters was the defending champion, but withdrew due to an abdominal injury.
Ana Ivanovic was the defending champion, but decided not to participate.
Petra Kvitová was the defending champion, but she decided to play at the Hopman Cup instead.
Alicia Molik was the defending champion, but was unable to compete due to vestibular neuronitis.
Sara Errani was the defending champion and she retained her title, beating Carla Suárez Navarro in the final, 6–0, 6–4.
Yvonne Meusburger was the defending champion, but lost to Chanelle Scheepers in the second round.
Venus Williams was the defending champion, but lost in the third round to Lucie Šafářová.
Flavia Pennetta was the defending champion, but lost in the quarterfinals to Sabine Lisicki.
Serena Williams was the two-time defending champion and successfully defended her title, beating Carla Suárez Navarro in the final, 6–2, 6–0. Williams won the title for the record 8th time in her career. This is also the second to last WTA tournament played by Nicole Vaidišová, who received a wildcard and lost to Simona Halep in the second round.
Ana Ivanovic was the defending champion, but lost in the second round to Michelle Larcher de Brito.
Serena Williams was the three-time defending champion, but lost in the fourth round to Svetlana Kuznetsova.
Elena Vesnina was the defending champion, but lost in the third round to Angelique Kerber.
Andrea Petkovic 
Carla Suárez Navarro 
