The margins are so small when Andy Murray plays Novak Djokovic that the details often make the difference.
Yesterday, Murray ran out of energy in a match that was influenced by an unruly feather, a blistered toe, and above all the scheduling that required him to play eight hours of the most gruelling tennis in the space of just over two days.
This is not to say that Djokovic did not deserve the victory, for he played magnificently once he hit his stride in the second-set tie-break.
Just as Murray was favoured by the order of play in New York – which gave him an extra day to recover for the final – so he got the short end of the stick here.
Murray's 7-6 6-7 3-6 2-6 defeat must feel all the more galling because he was the better player in the first set.
He came out striking his groundstrokes with perfect timing, bullying the ball and reducing Djokovic to frustrated gesturing in the direction of his players' box.
Perhaps Djokovic was feeling a little stressed about defending his title, and going in as the favourite, because he was unusually erratic in those early stages.
He failed to land a single first serve in the first-set tie-break, which he lost 7-2. The match began to change direction early in the second set, when Murray held three break points at 0-40 and could not take advantage.
There are always individual shots that stick in the mind after matches of this intensity.
In last year's final, Rafael Nadal missed a straightforward backhand putaway that helped a fading Djokovic back into the fifth set.
This time the key stroke came earlier, on the second of those three break points, when Djokovic mistimed a forehand and presented a slow, high-bouncing ball in mid-court for Murray to wallop for a winner. Unfortunately, his backhand drive slid a foot wide.
"He missed an easy backhand," Djokovic said after the match. "I relaxed mentally after that game. I became more aggressive and did not allow him to dictate."
The next flashpoint – or maybe it was more of a slow death – arrived at 2-2 in the second-set tie-break. Murray missed his first serve, and then as he moved to throw the ball up again, he noticed a feather floating down in the air in front of him – an unwanted gift from the seagulls who had been cawing furiously in the rafters and making Melbourne sound more like Newquay in holiday season.
As one wag noted, Ivan Lendl had prepared his charge for many things, but advice on the mating patterns of the local bird life was sadly lacking from the pre-match briefing.
"I mean, I could have served," Murray said. "It just caught my eye before I served. I thought it was a good idea to move it. Maybe it wasn't because I obviously double-faulted. You know, at this level it can come down to just a few points here or there.
"My biggest chance was probably at the beginning of the second set, and I didn't quite get it."
Djokovic won that tie-break 7-3 to level the match, and then came the big reveal, as Murray called the trainer to administer tape and padding to a huge blister on his right instep.
The Serbian did not sit down at that changeover, but stood stretching out his hamstrings.
One ancillary benefit of this was that he got a good look at what was going on in Murray's shoe. He could see the sickly yellow colour of the antiseptic salve, and he could see pieces of loose skin being snipped off by the trainer.
When you consider the speed of the players' movement in the first two sets, and the length of the pounding rallies – which averaged an extraordinary eight shots at the start of the match – any kind of physical disadvantage was sure to tilt the balance of power.
There was a psychological impact too.
As Murray's footwork faltered, Djokovic must have known that, if the match went to five sets like their previous two grand slam meetings, he would have the deeper fuel tank.
That knowledge helped him relax even further, and stroke the ball with greater fluency. Perhaps the key statistic was that Djokovic came to the net no fewer than 41 times, and won 35 of those points – an extraordinarily high ratio against a player with Murray's counter-attacking gifts.
The situation soon grew worse still for Murray as he began to clutch at his left hamstring. Phantom aches and pains have long been a Murray trope when he is losing, but in this instance he did seem to lose a tiny increment on each stride.
Djokovic was rolling now and he barely missed a ball as he scored the first service break of the match to go 5-3 up in the third set. The crucial point was a 36-shot rally that Djokovic closed with an inside-out forehand winner.
As the match moved past the three-hour mark, he did exactly what the ex-players recommend, which is to sprint for the finish line. (© Daily Telegraph, London)