Andy Murray and Novak Djokovic meet for the 35th time on Sunday in a match loaded with more significance than even some of their many contests for majors: the championship of each other, as someone once described the trilogy of world heavyweight title fights between Muhammad Ali and Joe Frazier.

They have not absorbed as many physical bruises as did those fine, departed warriors, but there has been pain, psychological as well as physical, since they first played as youths nearly 20 years ago and kept punching all the way through their professional careers, with Djokovic ahead in these surely latter stages of the rivalry, 34-10. “This maybe is one of the biggest matches that we have ever played against each other, so let’s enjoy it,” said the Serb.

Andy Murray suffers for his art in marathon win over Milos Raonic Read more

Murray has won two of his three slams by beating Djokovic in the final but this match is different. It has its recent genesis in Djokovic’s surprise collapse in the early stages at Wimbledon and has been building by the week, as he struggled on and off the court while Murray went on the sort of run every player dreams about: unbeaten now in 24 matches over more than three months and returning in front of his home fans with four titles collected on the spin among eight for the year – plus the scalp of the man who will look across the net at him around 6pm at the O 2 Arena on Sunday.

At stake is the world No1 ranking, which the Scot took from the Serb in Paris nearly a fortnight ago. Their almost inevitable collision follows semi-final wins that could hardly have been more different, Murray taking a record three hours and 38 minutes to wear down the serving monster that is Milos Raonic, 5-7, 7-6, 7-6, before Djokovic’s one hour and six minutes stroll to blow away Kei Nishikori 6-1, 6-1. There was very little traffic on Route 66.

Much will depend on how the two players recover: Murray’s match was the longest of the week (and in the history of the tournament), while Djokovic’s was the shortest.

The Serb was awesome, back to his best, and will be so tough to beat. He said later: “I pretty much executed everything that I tactically planned to do.

“I started off very well. That helps when you’re playing against a top player. Kei was obviously a little bit tired, not at his best. My week has been going in the right direction. The last couple of matches have been pretty much flawless and now we’re coming up to the last match of the year, the one everyone wanted. There are two of us on the court, let’s start with that. Let’s enjoy the occasion, be conscious of the great match. I’m honoured to be part of the history with Andy tomorrow. We have known each other many years.”

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The biggest struggle of the match arrived in the first set when security guards grabbed a spectator who ran on to the court and escorted him from the premises. Djokovic said, “No, I did not feel threatened. Maybe he just wanted to be noticed.”

The second semi-final was a pointed statement – not necessarily intentional – as Nishikori engaged in a three hours and 20 minutes game against Murray on Wednesday night, to that point the longest match in the tournament’s history. There was precious little left of the Japanese player against Djokovic, whose confidence and power have blossomed by the day after an uncertain start last Sunday.

There are some who still regard him as the world’s best, whatever the slim lead Murray has over him in the rankings. Others closer to the heat of battle see it differently; Raonic for instance.

“He’s done a lot of great things,” the Canadian said of Murray, clearly exhausted after what was one of the most draining spectacles – for players and spectators alike – this season. “Nothing’s missing in that storyline.

“Tennis ranking is a game of checks and balances. Who’s going to finish No1 is who does the best that year.

“Doesn’t matter whether [Murray and Djokovic] played or not. You could take that away from Andy in a way; then you could also say it’s sort of Novak’s responsibility to get to that point because Andy was there every single week. Regardless, Andy’s still the best player in the world of 2016. There’s no question about it.”

If Nishikori was totally spent after enduring a Murray mauling, the question remains unanswered about what the winner of the first semi-final can bring to the final. Raonic did not lack for candour about his own physical state. “I’ll probably feel like crap for the next few days,” he said.

Murray was more circumspect, not wanting to give Djokovic even a sliver of a psychological advantage, but he could not deny he was spent after a match that demanded as much mental fortitude as physical stamina.

“I don’t know how I’ll feel tomorrow,” he said. “Obviously I’m tired just now because it was a really hard match. It wasn’t just that it was physically hard, it was mentally a tough match, too. It was pretty stressful. I was quite far behind in the second set, a set and a break down, managed to turn it round. Then it was back and forth in the third set.”

The pressures also bring frustration. Earlier in the week, Djokovic was castigated for hitting a ball into the crowd, risking censure at least, not to mention injury to a spectator. His local media went apoplectic when a British journalist questioned him about it. “You guys are unbelievable,” he said in an exchange that was pretty feisty.

Well, Murray hit a ball into the crowd on Saturdaylast night, off an overhead beam admittedly, but conceded later: “If you hit balls into crowds, stuff like that, obviously you’re close to getting defaulted. You have to be very, very careful with that. That’s happened to my opponents this week, as well, and they didn’t get warnings for hitting a ball up into the scoreboard.

“I think for the players, you just want the consistency there. But, if you’re hitting balls into the crowd or anything like that, you deserve to be warned. It’s up to the umpire, if you hit a ball into the crowd, if it hits someone, whether they default you or not.”