US Open 2018: Novak Djokovic, a master of reacting, could serve as the perfect example for the still-learning Serena Williams

Are human beings reactive by nature, or proactive?

I suppose the easiest answer is that it differs from person to person. While some individuals thrive when they are in complete control of their own destiny, others are at their best when they are responding to external stimuli.

As the final weekend of the 2018 US Open showed, nobody responds to external stimuli better than Novak Djokovic. But did it also show that nobody responds worse than Serena Williams?

In Djokovic's case, the reactive powers are never more evident than in his play on the court. With him, everything always starts with the return.

The number of points he wins with returns that land right at his opponent's feet is staggering. Against Juan Martin del Potro in the final, Djokovic never seemed under any kind of threat because the Argentine didn't have the necessary firepower on the serve to win enough free points.

That may seem like an ridiculous thing to say about a 6'6" tank of a man who has been known to go entire matches without being broken. But that's just how good a returner Djokovic is; no matter how big Del Potro served, Djokovic always managed to send it back with venom.

The Serb's reactive abilities are evident in the rallies from the back of the court too, of course. I've often said that Djokovic's base level of play is possibly the highest of any player in tennis history; if that is true, it would partly explain why he engages in so many long rallies with seemingly no intention of making any change-up. But a bigger reason for Djokovic's inertia may be that his best play shows up when he's stretching himself in response to a particularly nasty thunderbolt from the opponent.

Del Potro hit a fair few missile forehands on Sunday which drew astonished gasps from the spectators in Arthur Ashe. But I eventually lost count of the number of points Del Potro lost after eliciting gasps; the bigger he hit, the more uncomfortable he seemed to be on the next shot.

As I watched Djokovic repeatedly swerve, spin, stretch and slide to wriggle the ball just out of Del Potro's reach, I began to wonder whether he has Ross Geller's immortal "Pivot, pivot, pivot!" line stuck on perpetual loop in his head. To those watching from the stands, Djokovic looks like a robot that pivots around his own axis, and also around the axis of every square inch of air on the court.

The Serb is nothing if not a master of maneuvering. His speed, flexibility and tennis IQ enable him to hit every shot with just the right amount of deviation and spin, forcing the opponent to come up with impossible shots point after point.

Djokovic's reactive nature is a part of his personality too. He regularly changes his behavior based on what he hears or sees from outsiders - most notably the spectators in the stands.

Mid-way through the final, the unusually pro-Del Potro crowd seemed to realize that their man wouldn't be able to beat Djokovic without a little outside help. So they decided to make even more noise than they were already making, and tried disrupting Djokovic's rhythm with catcalls and what-not - especially when he was serving.

The Serb is no stranger to being the less favored player on the court. And while he lost his focus for a while on Sunday as he tried to shush the crowd, he knows better than anyone how to react to negative energy, and channel it into something positive.

By the third set, he was practically using the "Ole, ole, ole, ole, Del-po, Del-po!" chants as fuel to rediscover his blindingly brilliant form circa 2015. He seemed to be going from strength to strength as Del Potro wilted at the other end, and he finished the match with a flourish.

Djokovic is always reacting to everything that's happening around him, and years of practice have made him a master of it. Why, then, does Serena Williams - who is six years older and has far more experience on the professional tour - still find it so difficult to react the way a champion should?

Serena Williams

Given the facts, it's hard to argue that Serena was anything but unsportsmanlike at best and thug-like at worst in the women's final on Saturday. While the initial violation for illegal coaching by umpire Carlos Ramos might be considered harsh by some, there is no denying that he followed the rule-book to the T and was fully within his rights to penalize Serena's unsavory conduct.

As Martina Navratilova so eloquently put it, Serena was wrong - about more things than one.

The debate about the supposed sexism - or racism, depending on your point of view - in the incidents that unfolded on Saturday is still raging on, and will probably continue for a couple of weeks more. But what I find more intriguing is that even after 20 years on the tour, Serena continues to behave like a spoiled child when things don't go her way.

The 23-time Slam champion - the GOAT across genders in my opinion - plays her tennis in a fashion that is almost the exact opposite of Djokovic. Serena doesn't react; she acts. Starting with the serve, the American has made a glittering career out of taking each point by the scruff of the neck.

When you play Serena Williams, you play on her terms.

So it was perhaps understandable why, in her younger days, she was inclined to throw the occasional tantrum when she tasted defeat. She once expressed the opinion that she had lost to Justine Henin because the latter hit some 'lucky shots', and it wasn't uncommon to hear the American say she was less than 100 percent whenever she succumbed to an inferior player.

The scary part is that she has been right on most such instances of ill-advised self-glorification. Serena is so much better than the rest of the field that beating her does require some amount of luck. But that seems to have insulated her to the necessity of always being gracious in the face of defeat (for the most part, she IS gracious; her unsportsmanlike side only comes out in moments of real stress).

In other words, Serena doesn't always know how to react when the element of control - or at least the illusion of it - is taken away from her hands.

In the final against Naomi Osaka, she was getting beat. Osaka was clearly the dominant player on the day; she was serving better and controlling a majority of the rallies with her sublime shot-making. That had already put Serena on the backfoot, so when the point penalty for her second infraction of the day came about, she seemed to have no control left whatsoever.

Unable to assert her game on the proceedings - no amount of power in your strokes can win you back a point penalty - Serena didn't seem to know what to do, or how to react. That she chose possibly the worst way to channel her frustration is beyond doubt; calling someone a 'thief' for following the rule-book is hardly the most healthy way to compete in a Grand Slam final.

When you are not accustomed to being in a particular situation, you tend to make a mess of it. And God knows Serena is not accustomed to being the 'reactive' party in any tennis match.

But you'd think that after so many years on the tour, and getting close to the age of 40, AND becoming a mother, she would've been given enough lessons on how to read the room and behave in a manner befitting a champion.

Her tirade against Carlos Ramos was thoroughly unbecoming, and brought tennis into the news for all the wrong reasons - much like the infamous outbursts of Nick Kyrgios and Fabio Fognini. I won't even get into how unfair the whole episode was on Osaka, who was merely trying to give her best on the biggest day of her career.

The actions of Ramos may or may not have had a sexist twinge - I personally don't think they did - but a woman of Serena's experience should've known he was well within his rights to give her a code violation (or three). If she thought she could call a well-respected umpire a thief and get away with it, just because male players get away with that kind of stuff, then it makes us wonder whether she has grown up at all in the last 20 years.

That's the thing with growing up though; it necessitates reacting to the changes around you, and tailoring your behavior accordingly.

Novak Djokovic has reacted in exemplary fashion to everything that's been thrown at him over the past decade. It's time Serena learned how to do that too.