I have loved sports all my life. I have watched playoff hockey among 21,000 towel-waving, obscenity-screaming, passion-choked Montreal Canadiens fans. I have stood in the rain for nearly four hours to see my Dallas Cowboys grind out an overtime win. Earlier in August, I sat in Montréal’s Uniprix Stadium and watched as Rafael Nadal, the second seed in this year’s Rogers Cup, fell to 18-year-old Canadian Denis Shapovalov. Two days later, I had the privilege of seeing Roger Federer up close — and it was unlike any sports experience I’ve had in my life.

There was nothing outwardly spectacular or dramatic about the match I attended: no records were set, no milestones were reached. This was not one for the history books. Federer dispatched 30-year-old Dutchman Robin Haase in 75 minutes. There is no statistic to which I can point that set this match, nothing substantive that can justify the sheer awe I felt. But this match stopped me in my tracks and turned me into a wide-eyed, head-in-the-clouds zombie for the rest of the weekend. It also made me think about sport itself and what makes it so universally compelling. Only one thing made this match different than others I’d seen: the genius of Federer in the flesh.

Federer, winner of 19 Grand Slams, is the greatest men’s tennis player to ever live. And, having just turned 36, he shows few signs of slowing down. The beauty and elegance of Federer’s strokes are just about impossible to hyperbolize. His forehand is delivered from a lithe athletic crouch; he seems to move in slow motion, effortlessly guiding the ball into his opponent’s court. He serves at speeds varying between 120 to 130 miles per hour. His backhand is one of the most versatile shots in the game: he can flatten it out with scorching pace, send it careening crosscourt at impossible angles, or just as easily throw a slice skidding and slipping into his opponent’s feet. His serve has none of the stop-and-start jerking mannerisms of so many of his fellows — it’s smooth, supple, and distinctive, like a rubber band being stretched out and then snapped back into equilibrium with a crisp and satisfying ‘pop.’

Top-tier men’s tennis is all about angles: the modern power-baseline game revolves around a player’s ability to pull his opponent out wide, to force him to stray so far from the court to chase down one shot that he doesn’t have the time or stamina to recover position for the next one. High-level competition is like billiards on a human scale, with each player trying to work the angles of the court to his advantage. His skill in this area is ultimately what sets Federer apart. His movement on the court is nothing short of beautiful. Other players twist and contort, their shoes pounding the court as they move from side to side and screeching as they turn, but Federer seems to glide. Other players grunt as they hit the ball and wail as they chase it; Federer is stoic, almost expressionless. Watching him for a little over an hour, I saw a man who did impossible things with his body so effortlessly that it made me wonder what it means to have a body at all.

Sport is about the mastery of the self over the body. The concept wouldn’t be as interesting if our bodies weren’t constantly failing us. The body is delicate, needs constant attention, and despite our best efforts, it can fail drastically — and when the body fails, the mind tends to follow. Mortals like me are fascinated by sport due to the way it exemplifies the body’s absolute obedience to the mind. It is the translation of fanciful thought into physical space. Federer sees a ball shooting toward him and thinks, ‘In the next half second before that ball arrives, I will begin my backswing, shuffle backward two steps, swivel my hips, adjust my grip, and bring my racquet whipping around just as the ball bounces up to waist level so that it redirects at an impossible angle to the other side of the court and catches the back half of a three-inch thick white line painted on the floor 78 feet away.’ And then he actually does it. Any of us could think that; the difference is that his body obeys.

Understanding sport in this way leads to some interesting conclusions. It gives a compelling reason to condemn the use of performance-enhancing substances: what makes sport fascinating is the way the athlete can control his body via his mind, not via some drug. Anyone who supports the legalization or normalization of those substances, even in sports where use is already widespread, undermines the value of sport itself.

Sport is a way for us to reconcile ourselves to the fact that we are limited by our bodies. Perhaps more accurately, it’s a celebration of the individuals who have managed to stretch out the limitations imposed by their bodies far further than any of us could possibly manage. It’s a chance for us to revel in what can be accomplished when the mind conquers the body. We admire the athlete’s mastery of himself and marvel at the feats that his mind can compel his body to achieve.

The Greeks had chariot races. The Roman Empire had gladiators. Today, we have Sidney Crosby, Usain Bolt, LeBron James, and Roger Federer. They remind us that the body is not an unconquerable mechanism but a tool that can be bound to our will. And no one does that quite like Federer.