He spent yesterday afternoon practising as a bewildering glut of scenarios were being played out in the O2 Arena in London as Group B of the Barclays ATP World Tour finals was slowly taking shape.
The day started with the certainty that the 25-year-old Scot and Novak Djokovic had reached the semi-finals. The afternoon match provided the other two of the last four with Juan Martin Del Potro defeating Roger Federer in three sets, 7-6, 4-6, 6-3, ensuring both the Argentine and Swiss player would play on in Greenwich. The final part of the jigsaw had to be completed with the David Ferrer v Janko Tipsarevic match. Ferrer's 4-6, 6-3, 6-1 victory means Murray will play Federer, while Djokovic takes on Del Potro.
Sunday in London is an evocative time for Murray this year. Today he hopes to take another step towards his first world tour title, a championship that would come with a £1 million-plus cheque and the more substantial reward – for an already rich young man – of the kudos of being last man standing at the most elite tournament of the year. The confidence level of the world No 3 would be taken to a new level as his first proper holiday in two years appears gently on the horizon.
After that welcome respite from the rigours of the world tour, Murray will head to Miami for a training regime that can best be described as brutal before heading to Melbourne for the Australian Open.
But two other Sundays in the capital formed the Grand Slam champion this year. The first came when he lost the Wimbledon final to Federer on July 8 in four sets, after winning the first. He cried, he walked disconsolately from Centre Court but he was almost immediately revitalised by his coach, Ivan Lendl, who told him that he had stood up well to the rigours of a daunting test. He would never face a bigger match, said Lendl. The Scot was heartened by this response.
On another Sunday, August 5, Murray walked out on to Centre Court and thrashed Federer in the Olympic final. Gold was taken but it was gilded by the faith Murray now had in beating the best on the biggest occasion.
"Any time you win against the top players, it gives you a confidence boost and the last few matches I have played against Roger and Novak, I've had chances in all of them," said Murray after defeating Jo-Wilfried Tsonga to make the last four.
"They have not been matches where I've gone out and been outplayed so I think I've been playing the right way against them. Sometimes [things are] going to go your way, sometimes they aren't but if I make sure I do the right things on the court then I'll get my wins against them."
It was a Monday in New York that gave this theory the most powerful support. Murray defeated Djokovic in five sensational sets to win his first major.
It was a win that made Murray's year, maybe his life. There may be accusations of overstatement levelled at that sentiment but not by anybody close to the world No 3 who witnessed how much he put into the pursuit of a Grand Slam and how devastated he was by every near miss.
Asked if a tour finals victory would be the icing on a very substantial cake, Murray replied: "I'm happy with how the year has gone. It would be a great way to finish the year if I could win here. Whatever happens from now on, I've had the best year of my life so I'll try not to be too disappointed if I don't win but it would be a great way to finish the year, that's for sure."
And what was the best victory, the Olympics or that night on Arthur Ashe court before a roaring New York crowd?
"It's a tough one," he said. "When I won the Olympics at that moment that was obviously the biggest... when you're playing at the Olympics, you feel like you're part of a team.
"The whole nation's right into it. You feel like you're playing for them. So, from that perspective, that was the best.
"But then with the US Open, that was a goal I'd set myself since I was 17, 18 years old when I came on the tour and it's taken a long, long time, a lot of tough losses, to get there so from an individual point of view, I would say that that was the biggest moment."
The growth in Murray as a player and a personality was given a generous tribute by Federer after his loss to Del Potro yesterday. "He's got mentally a whole lot tougher," he said. "And physically it is no problem for him to hang tough and believe he can bring it day in, day out. He's tactically stronger too."
The winner of 17 Grand Slam titles also pointed to the Scot's rising confidence, saying: "Obviously the last six months have been great for him. But it is not just this year, people forget how consistent he has been for several years now."
Of the Olympic final, Federer said: "He was just better."
He added: "I always hoped he would have a reaction like this, to be quite honest, even if it did cost me a gold medal. I was disappointed with his reaction after the Australian Open final  when I beat him then he went on a bad spell. He didn't play so well. Instead of taking positives out of a great tournament, because he was playing great tennis, he took the negatives out of it.
"He did not make that mistake again after Wimbledon. That is the sign of a champion."
Today, with poppy on playing shirt, Murray will step out again on another London Sunday. The best year has the capacity to get better.