Novak Djokovic, Roger Federer and Rafael Nadal are set to tighten their private stranglehold on Wimbledon as rivals struggle to keep afloat as they bid to dethrone the sport’s A-list stars.

World number one Djokovic is the defending champion and chasing a fifth title at the All England Club. Federer, promoted to second seed, can win a ninth crown while two-time champion Nadal is seeking to complete a rare back-to-back Roland Garros-Wimbledon double.

Twelve months ago, Djokovic arrived at Wimbledon with his career threatening to spiral into decline.

Unable to shake off the effects of right elbow surgery, the Serb was ranked at 21, his lowest position for over a decade.

But two weeks later, Djokovic had captured the 2018 title to add to his 2011, 2014 and 2015 wins, becoming the lowest-seeded player to take the Wimbledon trophy since Andre Agassi in 1992.

Since then, he has been rejuvenated, going on to claim a third US Open and seventh Australian Open title.

The only blip was a rain-hit semi-final exit to Dominic Thiem at Roland Garros, a loss which ended his attempt to become just the second man to hold all four Slams at the same time twice.

“Coming off from the surgery, being unable to have consistency with results, this was a huge springboard for me, the win at Wimbledon last year,” said Djokovic.

Federer, chasing a 21st major, first played Wimbledon in 1999.

Pushing 38, he would be the oldest ever Grand Slam champion if he were to lift a ninth title.

The Swiss star is also just five wins from becoming the first man to register 100 victories at the same Slam.

But Federer is quick to praise the influence of Djokovic and Nadal -- between them, the trio have won 53 of the last 64 Slams.

“I think we definitely became better because of one another,” he said.

Federer starts on Tuesday against South Africa’s Lloyd Harris, who is making his Wimbledon debut.

Nadal, meanwhile, arrives in London on the back of a 12th Roland Garros title.

His 18th career major also meant he moved within two Slams of Federer’s all-time mark for the first time. The Spaniard, ranked two but -- much to his irritation -- seeded three was champion in 2008 and 2010. He is now trying to join Bjorn Borg by achieving the Roland Garros-Wimbledon double for the third time.

“I won here in 2010 after a very, very tough first couple of rounds. Sometimes that helps, especially in this event, that you arrive here without playing much on this surface,” said Nadal.

It’s been 17 years since anybody not named Djokovic, Federer, Nadal or Andy Murray captured the Wimbledon title.

That long-distant honour went to Lleyton Hewitt in 2002.

Thiem, Alexander Zverev and Stefanos Tsitsipas, who occupy the next three spots in the world rankings, have yet to get past the last 16 on Wimbledon’s grass.

Ashleigh Barty goes into Wimbledon buoyed, unlike her predecessor Naomi Osaka, by being world number one and with several of her major rivals struggling.

The engaging 23-year-old Australian -- who emulated compatriot Evonne Goolagong Cawley by becoming number one last weekend -- has yet to get beyond the third round at Wimbledon.

However, by winning the Birmingham tournament last weekend Barty showed she has the strengths to add the grass court Grand Slam to the French Open she won on clay and become the first Australian women’s champion since Goolagong Cawley’s second success in 1980.

With Serena Williams finally showing signs of age, Osaka looking exposed through poor form and two-time Wimbledon singles champion Petra Kvitova still easing back to top form after an arm injury, defending champion Angelique Kerber may be the biggest threat to Barty.

Barty, who took an unconventional route to becoming world number one by taking a time off to play cricket, insists she feels no pressure.

Osaka, for her part, says she is much more in the frame of mind she was when she won the Australian Open earlier this year than the stressed-out player who exited the French Open in the third round.

Agence France-Presse