DOHA: Caroline Wozniacki must wait at least one more day to become year-end world No. 1, after suffering a surprise defeat at the round robin stage of the WTA Championships here Wednesday. The in-form favorite, who had previously lost only two out of 33 matches and won five titles, was beaten 6-4, 6-3 by Samantha Stosur, the world No. 5 from Australia. Wozniacki had a great chance to reach break point in the ninth game of the first set, but after missing a relatively easy kill started to play as though under pressure. Wozniacki's difficulties began at four-all, 30-all, when she had the court at her mercy but from a position close to the net, drove the ball long. She hurled down her racket hard in annoyance. The following game saw Wozniacki serve a double fault to go set point down, and on her first big opportunity Stosur played a great point. Stosur imposed a difficult angle upon the Wozniacki backhand, and strode forward to finish the rally with a rousing drive volley. Stosur broke serve again for 3-1 in the second set when Wozniacki's straight backhand drive veered off the parallel into the tramlines. It was damage which the favorite never repaired. Earlier Kim Clijsters made a flawed but satisfactory start to her bid to win back the WTA Championship title she last won seven years ago, scoring a straight sets win over Jelena Jankovic of Serbia 6-2, 6-3. Earlier Zvonareva made an important step forward to reaching the final for the second time by winning a long and often superbly contested match with Victoria Azarenka 7-6 (7-4), 6-4. Isner reaches quarters In Montpellier, France, fifth-seeded John Isner of the United States moved to 999 aces for the season as he edged out French qualifier Adrian Mannarino 7-6 (5), 6-7 (5), 6-3 in the second round of the Open Sud de France Wednesday. The top two seeds also advanced to the quarterfinals with No.1 Nikolay Davydenko of Russia defeating Mischa Zverev of Germany 7-5, 6-3 and Jo-Wilfried Tsonga booking a spot in the next round by cruising past Portugal's Frederico Gil 6-3, 6-4. Jarkko Nieminen of Finland rallied from one set down to claim his first victory in six matches over Frenchman Florent Serra and reach the second round with a 6-7 (4), 7-5, 6-1 win. In the remaining first round match, Gilles Simon beat Nicolas Mahut 6-4, 6-4 in an all-French encounter. Melzer, Cilic in last 8 In Vienna, defending champion Jurgen Melzer and his opponent in last year's final, Marin Cilic, both reached the quarterfinals of the Bank Austria Trophy Wednesday. Melzer defeated Lukasz Kubot of Poland 7-6 (3), 7-6 (2), and Cilic beat Jan Hajek of the Czech Republic 7-6 (4), 6-2. In first-round play, Bjorn Phau had a surprise 6-2, 6-4 win over fellow German Florian Mayer. Youzhny advances In St. Persberg, defending champion Sergiy Stakhovsky lost in the first round to Germany's Benjamin Becker 6-4, 5-7, 6-4, and top-seeded Mikhail Youzhny advanced at the St. Petersburg Open on Wednesday. Youzhny handled Daniel Brands of Germany 6-4, 6-1. Fifth-seeded Viktor Troicki of Serbia, who won his maiden title at the Kremlin Cup Sunday, also was eliminated 6-3, 4-6, 6-3 by German veteran Rainer Schuettler. In the second round, third-seeded Janko Tipsarevic of Serbia beat American Michael Russell 6-2, 7-5, and fourth-seeded Yen-hsun Lu of Taiwan beat Potito Starace of Italy 6-2, 6-2. Ukraine's Alexandr Dolgopolov defeated Fabio Fognini of Italy 7-6 (5), 6
