If it's summer, it's Wimbledon

NOVAK DJOKOVIC (1)

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.

The 29-year-old world number one, champion at Wimbledon in 2011, 2014 and 2015, has become the unstoppable Slam machine. 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.

Djokovic is the first man since Rod Laver in 1969 to hold all four majors and aims to become the first man since Laver, also in 1969, to complete the calendar Grand Slam, a feat only achieved three times in the sport's history.

"I don't want to sound arrogant, but I really think everything is achievable in life," said Djokovic, who will start his title defence Monday against Britain's world number 177, James Ward.

ANDY MURRAY (2)

Andy Murray, seeded second for only the second time at his home Slam, will be looking for his third major after the 2012 US Open and 2013 Wimbledon trophies.

The Briton, just a week older than Djokovic, has performed better and better against the Serbian machine, defeating him in Rome and pushing Djokovic during their gruelling French Open final.

Yet the Serb can still lord his power over Murray, pointing to his 24-10 advantage over their career meetings. The Scot has lost 13 of their last 15 meetings, which includes an all-loss record against Djokovic in majors over the last three years.

The 29-year-old is desperate to finally tip the balance in his favour and so persuaded his former coach Ivan Lendl to resume their partnership after a two-year hiatus. Lendl was Murray's coach when he won Wimbledon, the US Open and the 2012 Olympics -- titles that included a win over Djokovic in each event.

ROGER FEDERER (3)

For the first time in 15 years, Roger Federer arrives at the All England Club with few pundits expecting the number-three seed to leave with the trophy after one of the most troubled seasons of his glittering career.

17-time Grand Slam champion Federer, tied with Pete Sampras on seven Wimbledon men's singles titles, is preparing to make his 18th successive appearance at the grass-court Grand Slam, but there is now a genuine sense of vulnerability about the 34-year-old as the ravages of time take their toll on his body.

A knee surgery in February was swiftly followed by back problems that kept him out of the French Open, halting his record run of consecutive Grand Slam appearances at 65.

He enters The Championships without a title in the year for the first time since 2000, but he will hope that the environment in his favourite hunting ground, where he has reached the final the last two years, will be a turnaround.

SERENA WILLIAMS (1)

Serena Williams finds herself under siege from revitalised rivals and an army of doubters as the defending champion starts her bid for a seventh Wimbledon title and a record-equalling 22nd Grand Slam crown.

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.

Her bid for a Calendar Grand Slam in 2015 was brought to a screeching halt by 300-1 outsider Roberta Vinci in the US Open final. In the aftermath of that chastening day in New York, Williams has appeared a more vulnerable figure.

This year she has won only one of five tournaments, in Rome in May, while enduring shock defeats in the Australian and French Open finals.

The oldest woman, at 34, to be ranked number, off-court interests have critics claiming Serena is no longer so focused on her tennis in the twilight of her glittering career.

GARBINE MUGURUZA  (2)

Garbine Muguruza is happy to steal the spotlight from fellow Spaniard Rafael Nadal as the French Open champion sets her sights on a return to the Wimbledon final.

Muguruza's French Open final victory over world number one Serena Williams brought her a first Grand Slam crown at the venue where Nadal won nine times.

The 30-year-old's decline has coincided with the rise of Muguruza and the 22-year-old, whose engaging personality seems ready-made for celebrity, appears to be relishing the limelight.

Muguruza's Wimbledon preparations have been less than ideal as she was beaten in the first round of her only warm-up tournament at last week's Mallorca Open by Kirsten Flipkens.

Even taking last year's run to the final into consideration, she still finds grass a tricky surface to master. However, Murguza will have to overcome her troubles with grass and stake her claim to a throne which at the moment is occupied by a very shaky Serena.