The Serbian superstar retired from his quarter-final overnight with Tomas Berdych 7-6 (7-2) 2-0, saying he could no longer bear the pain.

Djokovic had received repeated on-court treatment for a shoulder problem during the tournament, but confirmed “it’s the elbow that already keeps bothering me for over a year and a half actually”.

“It’s unfortunate that I had to finish Wimbledon, a grand slam, this way. I mean, if someone feels bad about it, it’s me.

“But I tried. I tried what I could do from yesterday, to get it in the condition where I’m able to play.

“I was able maybe for 30 minutes to play with some pain that was bearable, let’s call it that way. All the treatments and medication couldn’t really help.”

The 12-times major winner said there was no point in going on when his serve and forehand were so severely undermined.

“I spend probably about two hours, two and a half hours today on the table in between the warm-up and match, trying to do everything I possibly could to make me fit,” he said after his first mid-match retirement since the 2009 Australian Open.

“But it wasn’t to be. For an athlete, especially in an individual sport, there is no way out. If you don’t feel fit, unfortunately that’s it. There is no one to come instead of you.”

The second seed said the scheduling debacle that led to him having to play two days running hadn’t helped, but declined to make a fuss over it.

“At the end of the day, this is something I have to deal with and accept it,” he said, declining to say what his immediate treatment plan was.

“It’s not a time and place for me to talk about the details. I’m just going to talk with specialists, as I have done in the last year or so, try to figure out what’s the best way to treat it and to solve it, to find a long-term solution.

“Obviously short-term, it’s probably rest is most appropriate. We will see.”

As triple champion Djokovic and top-seeded titleholder Andy Murray followed Rafael Nadal out the exit gates, the door has blown wide open for Roger Federer to storm through and continue his extraordinary renaissance with an unprecedented eighth Wimbledon men’s singles crown.

With the last two of his heavyweight rivals crashing out overnight, Federer is tantalisingly close to adding another magical moment to his unparalleled career after surging into a record 12th semi-final at The All England Club.

The seemingly ageless Swiss avenged a five-set semi-final loss to Milos Raonic last year with a 6-4 6-2 7-6 (7-4) destruction of the big-serving Canadian.

Widely pensioned off after hobbling out of Wimbledon last year with a career-threatening knee injury, not even Federer could have imagined how ridiculously successful his 2017 season would be.

Triumphant at the Australian Open in his first tournament back after a six-month layoff, the 35-year-old father of four faces Tomas Berdych – not Djokovic – in the semi-finals as he bids to become the oldest grand slam champion in 45 years.

And so wildly dominant has Federer been this season – in which he also completed the Indian Wells and Miami Masters double – that a 19th major may not even be the exclamation mark to his grand career.

The world No.5 and highest-ranked player left in the draw, Federer fired a warning to the remaining three challengers after celebrating his 100th match on London’s hallowed grass courts in majestic fashion.

“I’m much better prepared for Wimbledon this year than last year,” he said after winning his fifth straight match without dropping a set.

“Last year I had a hard, hard time practising through the claycourt season.

“The grasscourt season was difficult because of the back issues I had, and the knee issues. I was really lacking practice really.

“Then the matches, I could never really play quite so freely last year just because… I’m more focused on how the knee’s behaving rather than how I need to hit my forehand or backhand, or what’s not going to be good for my opponent.

“This year I’m just a normal tennis player again.”

But there is nothing normal about what Federer’s doing.

A month shy of his 36th birthday, Federer’s 12th quarter-final victory eclipsed the long-time record of all-time great Jimmy Connors.

“I’m just so, so happy to be in another semi here,” he said.

“I can’t believe it – 100 matches. It’s a lot. I’m very happy that my body kept me going all these years.

“I’m very pleased with how I’m playing. I’m happy my dream run continues and we’ll see what happens next.”

If he sees off Berdych, the 11th seed and 2010 runner-up to Nadal, on Friday, Federer will face either Croatian seventh seed Marin Cilic or Murray’s conqueror, American Sam Querrery, in Sunday’s title decider.
-AAP