Serena Williams knocked out of Madrid Masters

Petrova, who has won 19 doubles titles, on Wednesday 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 on 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.

"I wasn't moving my fastest but all I could do was try and do the best. I don't know. I definitely wasn't at my best," said Williams, who criticised the tournament for its scheduling. "This isn't a player-favourite tournament, just to be honest. None of the players are really gung-ho about playing here."

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 ground strokes.

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.
"He is very unusual and very difficult to play against. He is very fast with his shots and he has a fast serve too," said Nadal."It was an important victory for me because for a moment the match wasn't under control."

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 end it's positive not having to play against Roddick, although I was looking forward to playing him, it would have been a fun match. But now I just have to be happy to be in the next round," said Lopez. 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.

"It was the best I have hit the ball in a long time. I felt comfortable on the court," Murray said. "I didn't serve that well in the first set, but in the second I started to serve a lot better and started to hit 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 6-1.

"It wasn't my best tennis," said Jankovic. "I can't expect myself to play so great, it's my first match here in Madrid and it's high altitude and all that but I got through and that is the most important thing. I get to play today."