When Novak Djokovic steps on court and hits a tennis ball, clarity reigns. French Open organisers, for instance, know that they do not require groundsmen to clamber onto court and sweep the lines after sets. The Serb will frequently dust them himself with his strokes.
When Djokovic starts to move, his calves flexing like cables, electricity comes to mind. Or as Muhammad Ali, who we are still mourning, once said: "I'm so fast that last night I turned off the light switch in my hotel room and was in bed before the room was dark."
On Sunday in Paris, Djokovic streaked across his baseline and hit forehands that travelled exactly 23.77m to land on Andy Murray's baseline. We see it so often from him that we have begun to forget its absurdity. Think of it as cross-stitching while accelerating. This man is creating a picture of precision.
To prove this is not a fluke Djokovic will swivel, stride, slide and strike a backhand which fails only by a foot - errant by his standards - to hit the baseline yet journeys perfectly all the way down the sideline as if the ball is magnetised to it. His mastery of velocity, angles and accuracy suggest that instead of the Coupe De Mousquetaires on Sunday they should have awarded him the Fields Medal. It is for brilliant mathematicians under 40.
If further evidence is required of Djokovic's technique on the move, then kindly, as Murray did, play a drop shot against him. Think of it as the non-verbal equivalent of trash-talking Michael Jordan. The result will hurt.
Is he not better than Federer and Nadal in their prime? If we dismiss nostalgia and conduct imaginary matches in our heads, does he win against them? As Federer would have against Pete Sampras, and Sampras against Boris Becker, for such is the cycle of sport. Of course, such contests are inconclusive but the fact that we can entertain the notion tells us where Djokovic has travelled.
The Serb will be going in reverse and then suddenly he will be moving forwards. BMW might wish to meet him to discuss gears. He will slide, stretch and flick the ball, as he did against Murray, so that it scrapes over the net and lands cross-court. On a line, of course. Which makes you think that more than by points or by titles, it is by inches that he is the best player on the planet.
The thrill of sport often arrives from the diversity of competing athletes. Ali the incomparable boxer was an artist who mastered a science; Djokovic is a tennis scientist who has turned efficiency into an art. How he shrugged off his uneven first-set play, found his rhythm and then oppressed Murray was breathtaking not only in its execution but in its inevitability. Only champions at the pinnacle seem to own an "on" switch.
Djokovic's ability to pressure rivals with precision is boring only to those who cannot conceive of its difficulty. He is, without diminishing Stephen Curry, a sprinting version of that three-point basketball savant, and if physicists have weighed in to discuss Curry's flight path and parabola, then perhaps Djokovic is deserving of a similar scrutiny. He is, after all, making us think of tennis differently.
Of all the acronyms in life, GOAT must be the silliest: an ugly composition of letters for a person with a uniquely beautiful arrangement of skills. At best we might say goats are hungry, tough, nimble and adaptable, as fine a definition of the Greatest Athlete of All Time that we might want.
Djokovic has entered that territory and by winning four Slams in a row - first done 78 years ago by Don Budge and last achieved 47 years ago by Rod Laver - he is reframing the very idea of what is possible in modern tennis. He is not, with 12 Grand Slam titles, the numerical equal yet of Federer (17) and Nadal (14) and yet he has advanced an entire game with a flexible body and an inflexible will.
He is such an evolved, high-speed interrogator that he makes us ask the most blasphemous of questions: Have we ever seen tennis like this? Is he not better than Federer and Nadal in their prime? If we dismiss nostalgia and conduct imaginary matches in our heads, does he win against them? As Federer would have against Pete Sampras, and Sampras against Boris Becker, for such is the cycle of sport. Of course, such contests are inconclusive but the fact that we can entertain the notion tells us where Djokovic has travelled.
As the Serb held up the trophy on Sunday, history of course came to mind. If Roland Garros the aviator, after which the Paris tennis premises is named, set world altitude records then Djokovic is similarly elevating tennis. At the end of the match, he drew a heart on court but really he owed the crowd no further offering. His tennis had simply been enough.