Unlucky Rafael Nadal goes out without playing a shot after victory for Alexander Zverev

Rafael Nadal suffered the most unnatural of exits from the O2 Arena on Friday night, as he was eliminated without playing a shot. But his old foe Roger Federer will continue to challenge for a seventh ATP Finals title this afternoon.

The complex permutations of Group Bjorn Borg meant that Nadal was relying on Daniil Medvedev to pull off a victory in the final round-robin match, scheduled for 8pm. The incentives for Medvedev himself were limited, however, as he had already been eliminated. He was all too relaxed as he went down to defending champion Alexander Zverev by a 6-4, 7-6 margin. The upshot is that today’s semi-finals will begin with Federer’s fourth match of the year against Stefanos Tsitsipas, the 21-year-old Greek who originally hit the big time by beating him at the Australian Open. In the second semi-final Zverev faces Dominic Thiem.

Meanwhile, Nadal will be on a flight back to Madrid, where he will join the Spanish team ahead of next week’s new-look Davis Cup finals.

Fortunately, Nadal is a master of positive thinking. He has needed to be, given that at least one foot specialist tried to talk him out of a professional sporting career while he was still a teenager.

Nadal came into the interview room after his own afternoon victory against Tsitsipas, which occupied nearly three hours. And although he did not yet know whether he would reach the semi-finals, he was pleased with the way his game has developed over the course of the week. “Preparations have been very short,” said Nadal, who was not able to serve in the build-up because of a strained abdominal muscle. “And is the worst tournament possible to arrive without the best preparation possible.

“The first day you play one of the best players of the world in a tough surface, so if you don’t arrive with plenty of confidence on your body and your movements and everything, things become much more difficult, no? I think I have been improving on my tennis every day. If I’m not in that semi-finals, I go to Madrid with positive confidence that I am playing better and better.”

As for Federer, he might not have won a major in 2019, but he will still start this afternoon’s semi-final as the favourite to land the next biggest prize after his stunning upset win over Novak Djokovic on Thursday night. That result met with the approval of at least 80 per cent of the O2 crowd. Federer has always been favoured here, to such an extent that he sometimes made even Andy Murray feel like he was playing an away match.

Another delighted observer was BBC commentator Tim Henman, who has long been an admirer of Federer’s net-rushing style – not least because he won his first six completed matches against the man now widely seen as the GOAT, or Greatest Of All Time.

Indeed, Henman admitted to feeling a little guilty about having predicted Djokovic as Thursday’s likely winner. “It was an amazing performance,” said Henman. “I was sort of disappointed in myself almost that we sit in the commentary box and try and write him [Federer] off. On an indoor court that’s playing a bit quick, that’s borderline naive.

“His serve was up by six or seven miles per hour. I think it was hotter in there last night, which might have made it a bit quicker. But every time he got the chance to pull the trigger from the baseline, he did. And he didn’t make many unforced errors. It was one of his very best performances I have seen.”

While the complexities might not have worked out for Nadal, he did go away with a giant silver cup, after the outgoing ATP president Chris Kermode presented him with the trophy awarded to the year-end No 1.

“I am super happy,” said Nadal in response. “After all the things  I went through in my career with injuries, I never thought at 33½  I would have this trophy in my hands again. It’s something really emotional for me, a lot of work in the shadows to be where we are today. Without all my team and family next to me, this thing would be impossible. Thank you for the support.”

Nadal’s feat means that there is a neat symmetry about the three giants who have dominated world tennis for the last decade and more. He, Federer and Djokovic have all now finished as year-end No 1 on five different occasions.