It’s been a long and successful year for the 20-year old from Denmark. Wozniacki becomes the 10th different woman to end the season on the top of the rankings. Injuries to Serena and Venus Williams helped Wozniacki achieve her goal, but as Wozniacki’s rivals and they will tell you she deserved it.

With the win, Wozniacki will now play in the semi-finals in Doha against either Kim Clijsters or Samantha Stosur. Vera Zvonareva of Russia is the other semi-finalist.

Belgium’s Clijsters beat Victoria Azarenka 6-4, 5-7, 6-1 in Thursday’s session, while Stosur, who was on a two match winning streak, lost 4-6, 6-4, 7-6 (4) to a tough Elena Dementieva of Russia.

Wozniacki admitted she wasn’t in top form on Thursday, but had enough to beat Schiavone, the 2010 French Open Champion. “I just hung in there and kept my focus and tried to get a little more aggressive and not let her dictate the game and that helped me through.”, said Wozniacki.

Clijsters who many think is the favorite in Doha was pleased with her play on Thursday, but expects to improve. “It was a good match and obviously disappointing to lose that second set. It was close,” Clijsters said.

Defending champion and number one seed Roger Federer cruised through his opening match by taking out Peter Luczak in three sets. Second seed Rafael Nadal also advanced in straight sets on his quest to a fifth Roland Garros title. Federer and Nadal are expected to keep on cruising, as their next opponents Falla and Zeballos don’t pose any threats.

Andy Murray and Andy Roddick have played the most dramatic tennis so far. After losing the first two sets, Murray defeated crowd favorite Richard Gasquet in a match that lasted over four hours. In the middle of the third set, it seemed that Murray was on his way to a straight set loss. However, Gasquet was visibly tired towards the end of the third set and Murray ultimately won the match due to better fitness.

Andy Roddick also had some trouble in his first round match against the Fin Jarkko Nieminen. After easily winning the first set, Roddick lost the next two sets. In the fourth set, Roddick was a few points away from elimination. However, Andy managed to pull out the fourth set in a tiebreak, and then comfortably won the fifth set 6-3.

On the women’s side, the only major upset was the elimination of last year’s finalist Dinara Safina by 39 year old Kimiko Date Krumm of Japan. Safina’s injured back, new coach, and the usual mental fragility was a formula for an ugly three set loss to one of the oldest players in WTA history. The Williams sisters and Justine Henin advanced through their first round matches comfortably in straight sets.