FORMER champion Maria Sharapova blamed injury after being dumped out of Wimbledon at the second round by unseeded Argentine Gisela Dulko yesterday.<br /><br />Sharapova, seeded 24, looked far short of the form that carried her to the title in 2004 as she slumped to a 6-2, 3-6, 6-4 defeat on Centre Court.<br /><br />The three-time grand slam winner suffered a woeful first set and was broken in the second before recovering to level the match. But the Russian, still recuperating from an injury lay-off that saw her plummet to 59 in the world, faltered again in a nervy decider. And afterwards she admitted being unable to match the South American physically.<br /><br />“It was unfortunate the timing of this being only my fourth tournament since the injury, but that is just the way it is,” said Sharapova. “It is tough to put the injury out of your mind completely.”<br /><br />Dulko, the world No45, claimed victory on her fourth match point, and toasted her finest win to date. “That was the biggest win of my career,” said the 24-year-old. “It has come in the most important tournament for me and to beat Maria who is a past champion here is a great day for me.”<br /><br />While Sharapova struggled, two-time champion Serena Williams marched into round three with a straight-sets win over Australia’s Jarmila Groth in less than an hour.<br /><br />Progress was similarly emphatic for Roger Federer, as the highest seeded man in the draw continued his campaign for a sixth Wimbledon single’s title. Federer eased past Spain’s Guillermo Garcia-Lopez 6-2, 6-2, 6-4 to set up a third-round clash with 27th seed Philipp Kohlschreiber, and admitted victory had been easier than even he anticipated.<br /><br />“I expected a much harder match because he’s been playing well,” said the Swiss. “On grass you never know so I was quite surprised I was able to win so easily today.”<br /><br />Fourth seed Novak Djokovic declared he was enjoying his dark horse status after sweeping past Germany’s Simon Greul 7-5, 6-1, 6-4. The 2007 semi-finalist said: “I’m aware of my qualities. I’m happy that people are not talking about me.”<br /><br />Fernando Verdasco, seeded seven, needed four sets to beat Belgium’s Kristof Vliegen, while ninth seed Jo-Wilfried Tsonga strolled into round three when Simone Bolelli withdrew.