LONDON (AFP) - Rafael Nadal played down his chances of matching Roger Federer's Grand Slam haul here Sunday, saying the likelihood of reaching his rival's record of 16 titles remained "a dream." After adding four more Grand Slam titles in the past year the 25-year-old Spanish world number one now has 10 to his name and will be targeting an 11th at Wimbledon over the next fortnight. Victory at the All England Club would see Nadal move alongside Bjorn Borg and Rod Laver in the all-time standings, one behind Roy Emerson on 12, three behind Pete Sampras (14) and five behind Federer. But Nadal dismissed suggestions that Federer's record was in his sights here Sunday, saying he was "very far" from the Swiss master's benchmark. "I am not close to the 16 of Roger," Nadal said. "Sixteen is a lot. We can dream about a lot of things. For me it's a dream. May be not for you." Reigning champion Nadal -- who opens the defence of his title with a first round match against American Michael Russell on Centre Court here today (Monday) enjoyed a stellar 2010, scooping the French, Wimbledon and US Open crowns. Nadal meanwhile is already eyeing the defence of his Olympic gold medal next year, when Wimbledon will host the tennis tournament of the 2012 London Games. "The Olympics are a very special event. The experience that you can live on the village, and, you know, live these moments with the rest of the sports people, that then is something special," Nadal said. Meanwhile, Serena Williams believes it will be hard for her and sister Venus to make a winning return at Wimbledon because the women's tour is stronger than ever. Serena returned to action for the first time in 12 months after serious health problems at Eastbourne last week, while Venus also returned to competitive play at Eastbourne following a five-month hip injury absence. The return of the sisters has been seen as bad news for the rest of the women's tour, especially at Wimbledon where the American siblings have already amassed nine titles between them. There has been a Williams in 10 of the last 11 singles' finals in south-west London and it is hardly surprising that they are favourites to win the grass-court Grand Slam again. "I really just missed not being around the tour," she said. "I missed the ladies in the locker room. I missed laughing. I missed having matches. I missed the tour. I'm not sure if the women's tour missed me. I mean, maybe some extra color, I guess"