The Women's Tennis Association has ranked her World No. 1 in singles on 4 separate occasions. She became the World No. 1 for the first time on Aug 22, 2005 and last regained this ranking for the fourth time on May 19, 2008. She is currently ranked World No. 6.
Maria Sharapova made her professional breakthrough in 2004 when, at age 17, she upset two-time defending champion and top seed Serena Williams in the 2004 Wimbledon final for her first Grand Slam singles title. She entered the top ten of the WTA Rankings with this win. Despite not winning a major in 2005, Sharapova briefly held the number one ranking, and reached three Grand Slam semifinals, losing to the eventual champion each time. She won her second major at the 2006 US Open defeating then-World No. 1 Amélie Mauresmo in the semifinals and World No. 2 Justine Henin in the final. Sharapova's 2007 season was plagued with a chronic shoulder injury, and saw her ranking fall out of the top 5 for the first time in two years. She ultimately won her third Grand Slam at the 2008 Australian Open, defeating Henin in the quarterfinals and Ana Ivanović in the final. After reclaiming the number one ranking in May 2008, Maria Sharapova's shoulder problems re-surfaced, ultimately requiring surgery in October and forcing her out of the game for nearly ten months. Maria Sharapova returned in May 2009 and was ranked No. 126 in the world due to her extensive lay-off. Since her comeback, Maria Sharapova has won 4 singles titles (bringing her career total to 23) and improved her ranking to within the top 10.
Maria Sharapova's public profile extends beyond tennis, as she has been featured in a number of modeling assignments, including a feature in Sports Illustrated Swimsuit Issue. She has featured in many advertisements including those for Nike, Prince and Canon and is the face of several fashion houses, most notably Cole Haan. Maria Sharapova was the most searched-for athlete on Yahoo! in both 2005 and 2008. Since February 2007, she has been a United Nations Development Project Goodwill Ambassador, concerned specifically with the Chernobyl Recovery and Development Programme.