ranked Serena Williams was knocked out of the Madrid Masters Wednesday, falling 4-6, 6-2, 6-3 to Nadia Petrova of Russia in the third round. Petrova, who has won 19 doubles titles, frustrated Williams into making 41 errors by hitting accurately from the baseline. The 16th-seeded Petrova served 10 aces to advance to the quarterfinals. Williams had looked out of form in a marathon match against Vera Dushevina Tuesday, which lasted 3 hours, 26 minutes. It was the longest match of her career. Last year, Williams was beaten in the opening round in her first appearance at the Madrid Masters. Second-seeded Rafael Nadal advanced to the third round with a 6-4, 6-3 win against Ukrainian qualifier Oleksandr Dolgopolov Jr. Nadal broke early to take control of the first set, although Dolgopolov pressured the Spaniard's serve in the second with some blistering groundstrokes. A superb forehand down the line by Nadal gave him a breakpoint which he converted to go 4-3 up in the second. Dolgopolov saved a match point serving at 5-3 down but Nadal still broke to close out the match. Nadal was in the Madrid Masters on the back of tournament wins in Monte Carlo and Rome. The 2005 champion and 2009 finalist is hoping to extend the record for ATP World Tour 1000 titles of 17 he shares with Andre Agassi. At 21, the 62-ranked Dolgopolov is the youngest player in the ATP top 100. Earlier, fifth-seeded Andy Roddick withdrew from the tournament before his second-round match against Feliciano Lopez due to illness. Lopez instead played and beat Spanish countryman Oscar Hernandez, who failed to qualify. In the third round the Spaniard plays Ernests Gulbis of Latvia, who beat 10th-seeded Mikhail Youzhny of Russia. Seventh-seeded Jo-Wilfried Tsonga withdrew injured from his match with Guillermo Garcia-Lopez after losing the first set 6-2. Spain's Nicolas Almagro upset fourth-seeded Robin Soderling of Sweden 6-4, 7-5 to set up a meeting with Juan Monaco of Argentina. Andy Murray, the 2008 winner, enjoyed a smooth passage through to the third round, beating Argentine qualifier Juan Ignacio Chela 6-3, 6-3. The third-seeded Murray hit 32 winners. Other winners were John Isner of the United States, who plays Nadal in the next round, and Stanislas Wawrinka of Switzerland. In the women's draw, fourth-seeded Venus Williams beat Francesca Schiavone of Italy 3-6, 6-1, 6-2 to move into the fourth round. In the second round, seventh-seeded Jelena Jankovic beat fellow Serb Ana Ivanovic 4-6, 6-4, 6
