Federer was undone by the French Open in 2004, 2006 and 2007 while Nadal’s failure to win the 2010 Australian Open was a blip in a year when he romped to victory in Paris, London and New York. Having finally rid himself of his French Open curse, Novak Djokovic is chasing a third successive Wimbledon title to move one step closer to the first calendar Grand Slam in 47 years. Serbia’s Novak Djokovic practises at the All England Lawn Tennis Club on Saturday.Since she walked off Wimbledon’s Centre Court cradling the Venus Rosewater Dish awarded to the women’s champion nearly 12 months ago, Williams has found herself engaged in a losing battle with the history books.With Maria Sharapova absent as she appeals against a two-year ban for doping, the main challengers for Serena’s crown should be second ranked Muguruza, former Wimbl-edon finalist Agnieszka Radwanska and two-time Wimbledon winner Petra Kvitova.Djokovic currently holds all four majors and is targeting becoming the first man since Rod Laver in 1969 to complete the calendar Grand Slam, a feat only achieved three times in the sport’s history.His victory over Andy Murray in Paris gave him a 12th major, taking him to within two of Rafael Nadal’s mark and five behind the record 17 of Roger Federer.Murray, just a week older than Djokovic, will be looking for his third major after the 2012 US Open and 2013 Wimbledon trophies.He is the first man since Jim Courier in 1992 to win the Australian and French Opens back-to-back.The 29-year-old world number one, champion at Wimbledon in 2011, 2014 and 2015, has become the unstoppable Slam machine.In between practice and this week’s rain, he posed for ‘selfies’ on the London underground, happily opting for public transport despite becoming the first man to pass the $100 million prize money mark at Roland Garros.. 2 Murray, the 2013 Wimbledon champion, remains Djokovic’s only serious rival but the British star has a 10-24 career record against the Serb.Even Federer and Nadal failed to achieve that sequence just as the two greats were also unsuccessful in attempts at a calendar sweep. “I don’t want to sound arrogant, but I really think everything is achievable in life,” Offset Double Ring Ratchet Spanner said Djokovic, who appears to be under little pressure heading into Wimbledon where he starts Monday against Britain’s world number 177, James Ward. Serena battles rivals, self doubtSerena Williams finds herself under siege from revitalised rivals and an army of doubters as the defending champion starts her bid for a seventh title and a record-equalling 22nd Grand Slam crown.”Djokovic has reached at least the quarter-finals of every Slam since a fourth round exit at the 2009 French Open.Having finally rid himself of his French Open curse, Novak Djokovic is chasing a third successive Wimbledon title to move one step closer to the first calendar Grand Slam in 47 years.But her historic bid came to stunning end in the US Open semi-finals when she was beaten by 300-1 outsider Roberta Vinci.“I’m trying to cherish these moments.But Nadal is missing from this year’s Wimbledon, nursing a wrist injury, while seven-time All England Club champion Federer is without a major in four years and a shadow of the player he once was.That Wimbledon final victory over Garbine Muguruza meant Williams had won all three of the year’s major titles, putting her within touching distance of becoming the first woman to secure a calendar Grand Slam since Steffi Graf in 1988. Whether or not I can reach a calendar slam, that’s still a possibility.World no.