(CNN) -- Argentina's unseeded Gisela Dulko caused an upset on Centre Court with a battling win over former champion Maria Sharapova.
Gisela Dulko of Argentina celebrates beating Maria Sharapova of Russia at Wimbledon.
The 24-year-old fought through the nerves to complete a 6-2, 3-6, 6-4 victory to seal her place in the third round and dump one of the biggest names in women's tennis out of the championships.
Though the Russian Sharapova, who won the grass-based grand slam in 2004, was seeded 24 for Wimbledon due to her season blighted by a shoulder injury, the result was still an upset.
The 24-year-old South American, who has reached the third round on three previous occasions at Wimbledon, now faces another Russian in her next match in the form of tenth seed Nadia Petrova who beat Dulko's doubles partner Shahar Peer of Israel 6-3, 6-2 to go through.
"It is the most important tournament in the world for me," she said in a court side interview after the match.
"It's been a great day and I feel really happy - I didn't play very good in one game and with players like Maria, you know she will take her chances.
"But in the third set I just kept on fighting - I was really nervous at the end and just wanted to finish the match as the winner - and now I'm so happy."
The crowd at the British venue warmed to the plucky Argentinean as the game wore on, a factor that Dulko said helped her to victory: "The crowd were fantastic with me and I'm really grateful."
Elsewhere, Serena Williams powered to victory brushing aside Australia's Jarmila Groth in a 6-2, 6-1 win. The second seed American will meet either Anastasia Pavlyuchenkova of Russia or Italy's Roberta Vinci in the third round.
Progression was also ensured for Japan's Ai Sugiyama with a 7-6 (7/5), 6-3 victory over Spanish qualifier Arantxa Parra Santonja.
The 33-year-old Sugiyama, who is ranked 38 in the world, recorded her previous best at the event in a quarter final appearance in 2004 and will now face Slovakia's Daniela Hantuchova who beat China's Zheng Jie.
Zheng failed to match her previous Wimbledon high of reaching the semifinals in 2008 falling to a 6-3, 7-5 defeat.
Meanwhile, in the other results from Day Three, eight seed Victoria Azarenka of Bulgaria thrashed Romania's Ioana Raluca Olaru 6-0, 6-0.
America's Jill Craybas lost 6-3,6-0 to Frances Virginie Razzano, while Slovakia's Dominika Cibulkova triumphed 6-2, 6-4 over Urzula Radwanska of Poland.
India's Saania Mirza went down 6-4, 6-4 to Sorana Cirstea of Romania while the all-Russian battle of Elena Vesnina and Vera Dushevina, saw the former win 6-3, 6-4.