LONDON (AFP) - Maria Sharapova shrugged off her shock Wimbledon second round defeat on Wednesday by insisting she can regain her membership of the women's tennis superpower club. The 2004 champion slumped to a shock 6-2, 3-6, 6-4 loss to Argentina's Gisela Dulko on Centre Court in just her fourth tournament since returning after a 10-month injury lay-off following shoulder surgery. It was her second successive loss at the last 64 stage at the All England Club, but she refused to be written off as a spent force. "You think of these injuries as basically preventing you from playing your sport. But if you look at the bigger picture, there are many things that can happen that can limit you to doing things in life or even having a life," said the 22-year-old."But if you have a good head on your shoulders, you also know that there's a life to live and if you stay positive, everything's going to be all right, no matter what and no matter how bad the injury is." Sharapova reached the French Open quarter-finals and the semi-finals of the Birmingham grasscourt tournament where her opponent Li Na of China claimed that the Russian had lost some of her trademark power during her absence. But the former world number one, whose ranking is now down at 60, insists that her recovery is a gradual process and that just being at Wimbledon is an achievement in itself. "I wasn't kidding when I said just being here is a wonderful accomplishment," said Sharapova. "I'm not lying about it. I had the pleasure of playing on Centre Court again. "I didn't play on it last year. The losses are tough but more here than at any other tournament. But it puts some perspective into your life. It's all right. I have many more years ahead of me. "It's just unfortunate, the timing of my comeback and this only being the fourth tournament. I would have liked to have a longer season before coming here, but that's just the way it is."