What form does a champion assume after they leave the stage? What does your memory spontaneously associate with them? Is it a moment in time? Their gleaming record? An unforgettable attitude? A specific character trait? When Stan Wawrinka finally packs his racket away for the final time he will surely be remembered as a great champion, who emerged late but made a big impact on tennis. At 31, he has three Grand Slam titles from three different majors and that in itself is enough to forge his legacy.

And yet, more than his headline triumphs, in 10 years what will spring to mind when thoughts wander to Wawrinka is instead a physical gesture. A stroke. His one-handed backhand has been both a lethal weapon for Wawrinka and one of the defining shots of his era. “If there was a school just for backhands, I think he would be the model,” says Yannick Fattebert, one of his current coaches.

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You cannot simply reduce a player of Wawrinka’s talent and standing down to one single aspect of his game. But nevertheless, it will always be his signature shot. “You can't just talk about Stan's backhand,” says Fattebert. “There are other elements to his game. They are not as well catalogued as his super backhand. But it is still a matter of pride for him to have an exceptional shot, which is truly out of the ordinary.”

The man known as ‘Stanimal’ in fact enjoys a double benefit emerging from this one defining ability. Not only has he mastered the most technically pure of any shot in tennis, he also belongs to an endangered species - two good reasons to bless his backhand with a special aura. It is clear that the one-handed backhand has an almost artistic quality to it which sets it apart from any other shot. You will rarely, if ever, see anyone rave about a double-handed backhand. They are often effective, sometimes daunting, but if beauty is a subjective concept, it is almost without exception denied to the double-handed stroke.

What Wawrinka has succeeded in doing is refining the stroke to a degree never matched in the history of the sport, despite the one-handed backhand becoming scarcer than ever. If his trump card had been a first serve or a crushing forehand, it would not have left an imprint as strong as these are the usual calling cards of the 21st century tennis star. Not so with the single-handed backhand, which had been so marginalised over the past four decades that its complete disappearance is not outside the realms of possibility.

The Dead Poets Society

Today, the ‘one-handers’ are a brotherhood apart; a tiny committee; a Dead Poets Society of tennis. Wherever you look - top 10, top 20, top 50 or top 100 – you will find the same proportion of players using the technique: around 20%. Of the top 100 players in the world on December 31, a full 82 had a two-handed backhand and just 18 used one hand. It is a similar situation in the top 50, where the one-handed backhand is represented by 12 players.

The top 50 at the end of 2016 Image credit: Eurosport

In the current top 20 there are only five practioniers of the art: Wawrinka (4th), of course, but also Dominic Thiem (8th), Roger Federer (16th), Grigor Dimitrov (17th) and Richard Gasquet (18th). They are all players with a style which is more refined than brutal. The one-handed backhand is often a guarantee of elegance. “For the viewer, it’s great to watch,” adds Fattebert.

Aesthetically pleasing, yes, but in the current game, which is so defined by speed and power, it is often less effective than a conventional two-handed backhand. “If it’s only used to look pretty, then it is of no interest,” says Fattebert. “A player does not choose a shot in relation to its aesthetics but because, technically, it makes sense. Stan is attached to his backhand, and he realises his tremendous advantages, but he would love to have a two-handed backhand if it made him more effective.”

The stars of the one-handed backhand Image credit: Eurosport

The low proportion of current players using a single-handed backhand is the result of a process of conformity which has been almost constant since the mid-1970s. But what a reversal of history that transformative period was.

Originally, the one-handed backhand was a tautology. Everyone used it, and it was only in the 1930s that the first rebels emerged from Australia. Vivian McGrath was treated like an extraterrestrial when he showed off a double-handed backhand at the age of 17 in the 1933 Australian Open, when he reached the semi-finals with what was, at the time, such an unfamiliar stroke. Having won the Australian Open in 1937, he is considered the first major winner to have developed a double-handed backhand, but it was soon to be imitated by his compatriot John Bromwich. The two Australians became pioneers of a shot that would eventually sweep through the sport.

1974: The Year of the Revolution

At the time, who could have imagined that their revolutionary stroke would become tennis orthodoxy? It still took four decades for the double-handed backhand to dominate the sport and the year of the revolution, a season which marked a before and after in the history of the game, was 1974. That was the year in which Jimmy Connors, 22, won the ‘Small Slam’ of the Australian Open, Wimbledon and the US Open, and Bjorn Borg, 18, triumphed at Roland Garros.

Bjorn Borg, a prince of the double-handed backhand Image credit: AFP

Together, the American and the Swede marched tennis into a new era. Their seizure of power across all four Grand Slams was achieved with double-handed backhands; before that year, the previous 106 men’s Grand Slam tournaments had been won by players with single-handed backhands, stretching back to Bromwich’s coronation in Australia in 1946. Indeed, 1974 was also the year when Chris Evert made her definitive entrance onto the stage, winning her first two major titles with a Roland Garros-Wimbledon double.

These three titans of the sport emerged at a time when tennis was achieving mass popularity. Connors, Evert and most of all Borg were not only champions, but true stars. Their influence on tennis was colossal and from them, the two-handed backhand would spread like a tidal wave. A new standard was born. It is enough just to look at the 26 players who have occupied the world No. 1 spot since the ATP introduced the classification in 1973, just before Borg and Connors burst onto the scene. Of the first 13 No. 1s, spanning the time from 1973 to 1996, there were still eight players who possessed a single-handed backhand. In the 20 years after that, there were only three: Pat Rafter, Gustavo Kuerten and Roger Federer.

Number ones and one-handed backhands Image credit: Eurosport

The standardisation seen amongst elite players was being replicated at youth level. In 1987, Jack Kramer, a winner of four Grand Slam tournaments in the 1940s, sounded the alarm. “Young players lack the fundamental skills,” he told Le Monde. “It’s the Borg and Evert syndrome. But what works for Borg and Evert does not work for 90% of kids.”

For young players, the double-handed backhand is the easy way out. A backhand stroke is not natural, certainly not when compared to a forehand, and using two hands helps to compensate for a deficit in power on the reverse side. At shoulder height, in particular, the two-handed backhand is also easier to master. For a beginner, or for a child still yet to develop physically, it offers more speed and more security. Even Federer has admitted that he would teach his children to practice using the two-handed backhand.

Conversely, though, the single-handed backhand has much greater potential due to its superior variety. If it presents more risk, using one hand also promises greater reward. It almost involves an element of courage. It is a Pascal’s Wager about the existence of a glorious future. It is not a gift bestowed on everyone. This was notably expressed by Martina Navratilova, a former disciple of the one-handed backhand.

I would be teaching kids a two-handed topspin and a one-handed slice and volley. It practically takes a genius to hit a single-handed backhand.

Sampras: It was a tough decision, but I've never regretted it

Alain Solves agrees. A few years ago, when in charge of the Avenir National programme at the Federation Francais de Tennis, the technician studied the backhands of youngsters in training. “For men,” he told We Love Tennis. “The closer you get to the top, the fewer one-handed backhands there are. If you develop a single-handed backhand you have to have a weapon; you cannot get to the highest level with a weakness on the backhand side where the guy is always obliged to slice.”

The most famous case of a player changing their stroke is undoubtedly that of Pete Sampras. At the age of 14, on the advice of his mentor at the time, Peter Fischer, the man who would go on to win seven Wimbledon titles abandoned his Borg-esque backhand to play with one hand. It was a fateful choice which caused Sampras some initial problems but paid off in a huge way. As ‘Pistol Pete’ said, it was a decision which involved short-term pain for long-term gain.

“For two to three years I lost a lot of matches. My big rival was Michael Chang and I used to beat him, but when I gave up the two-handed backhand he started to beat me. But at 18 I became stronger physically and my one-handed backhand became a weapon. It was a tough decision, but I never regretted it.”

Pete Sampras in action in the 2002 US Open Image credit: AFP

Stefan Edberg, also thanks to the intuition of a coach, in this case Percy Rosberg, had a similar conversion in adolescence. It also had the same objective: to enhance his attacking capabilities. Indeed, the one-handed backhand, except in exceptional cases, is a weapon of the fearsome warrior. More recently, Dominic Thiem was also pushed by his coach, Gunther Bresnik, to cross the rubicon.

If the Austrian is not quite a parallel case to Edberg, he had also gone in search of a change in strategy after finding himself weighed down by the double-handed backhand. “His attitude, his personality, his game: everything was very defensive,” Bresnik told the Wall Street Journal last June. “The two-handed backhand would not have brought him anywhere, he would only have been an average player.” As with Sampras, the transition was a painful rite of passage. “I don’t think I won a match for a year, a year and a half,” smiles Thiem today.

In the mid-90s, the journey proved to be much calmer for Stan Wawrinka. The decision to switch was taken by his coach at the time, Dimitri Zavialoff, who remained by his side until 2010 after leading him to ninth in the world. "At the beginning, he had a two-handed backhand,” explains the Frenchman. Wawrinka was then only 11 years old. “But he wasn't comfortable at all with it. He couldn't find how to use his left arm properly. I said to myself ‘okay, let's try with a one-handed backhand, let's see if he can handle it’. From the first strokes, he successfully solved the problem with his left hand. And he quickly forgot his two-handed backhand. Of course, he needed time to find the proper stroke, the one that he has today, and it's been a lot of work. But at 12 years old, he was already very comfortable.”

A little more than that, even. The benefit of his new backhand shot was immediately obvious. Beyond the technical aspects of the new stroke, it also stirred up in Wawrinka something innate that cannot be coached. You either have it or you don’t, and with his new backhand, Wawrinka had it. Dimitri Zavialoff again: “He had a natural ability on the backhand side, a real ease to find the right distance form the ball and how to position himself. All that came to him more easily than it would to an average player.” Very quickly, the one-handed backhand established itself as a deadly weapon. It also gave him a reputation, as his old coach explains.

“His backhand caused some trouble for his rivals very quickly. Young guys like to target the backhand of their opponents because it's often the weakest link of their game. But not with Stan. It was a big asset, being able to do this backhand with one hand, and you had to realise that he had very special skills.”

Stan Wawrinka in 2002. Just 17 years old and already the stroke is so recognisable Image credit: Imago

The Terminator and Mozart

Those who saw him triumph in the juniors at Roland Garros in 2003 remember having been struck by this unique weapon. In the 13 years since it has both been constant and evolving. A paradox? Not quite. “From a technical standpoint,” says Eurosport expert Patrick Mouratoglu, “his backhand is very stable since the juniors, when he won the boy's title at the French Open in 2003 at the age of 18. But he did not then have the slice that he has now and that he uses to change the rhythm of a point. He was not able to do that a few years ago."

The French coach’s external perspective is supported by the testimonies of Zavialoff and Fattebert. “In the juniors, where he was relatively strong, it was above all in the shoulders because he was already extremely powerful from above,” explains his first coach, Zavialoff. “Then he only had to find a certain consistency to have confidence in his control – it was an important axis that his work hinged on. But he was not conservative in his way of playing, so he made mistakes.”

“His backhand has always been his main weapon, but I think it continued to change over the years, even the last few years,” says Fattebert. “He has even more options on it now than he used to have five or seven years ago. His slice has improved. Tactically, he knows how to use it with more efficiency. He finds better cross-court angles.” Wawrinka has changed in size and his backhand, even if it was already a key feature of his game, has not escaped this metamorphosis. “There has been a general evolution in Stan's game for three or four years and his backhand has been the beneficiary of this evolution, just like the rest of his game. Physically he's better too, so it allows him to be better placed on the ball, and exploit his backhand even more.”

Today, the Wawrinka backhand is almost unanimously recognised as the most iconic on the circuit. Now when we think about the one-handed backhand, we think of Wawrinka. "Stan's backhand is different from all the other one-handed backhands,” says Mouratoglu. “Primarily because it is his main strength, which is not the case for a player like Dimitrov, Federer, or Thiem.” The only other player whose main weapon is a single-handed backhand is Richard Gasquet.

Terminator Image credit: Eurosport

But if Gasquet possesses more variations and has a greater efficiency when returning, the phenomenal power deployed by the Swiss gives his stroke another dimension; it makes it fully realised. Watching a Wawrinka backhand is to have an almost physical experience. The noise produced on impact indicates the weight of the shot. He is the Terminator, while Gasquet is Mozart. You can prefer one to the other, it’s a matter of personal taste, but in today’s game, Arnie has more influence than Amadeus.

“It's the most powerful backhand on the circuit,” says Mouratoglou. “It combines rotational speed and ball speed, and this combination is what helps to make it unique. What is impressive about Stan is his ability to hit his backhand when he's just made a sprint. He can maintain perfect control, which requires a lot of core strength."

He can hit perfect backhands on the sprint in all situations, including, sometimes, the most unlikely, as with this extraordinary winner which passed around the net and into legend, in the final of Roland Garros against Novak Djokovic in 2015.

Thiem and Dimitrov, the heirs to the throne

Yannick Fattebert is reluctant to say conclusively whether the man he coaches is in possession of the best backhand in the game, but his admiration for the shot shines through.

“On a ball which is a little bit long, a player with a two-handed backhand or an average one-handed backhand, will be able to accelerate the ball, but only to a certain extent. Stan is able to play a winning shot with his backhand as if it were a forehand - and even with more power than many forehands. This ability to generate such power on long balls… there are very few players, all types of backhands combined, who are able to do so. I think he's the only one.”

Close to perfection in how it melds technique, power and control, the one-handed backhand of Stan Wawrinka is the most emblematic of its era. John McEnroe even considers it “the best of all time”. It’s all subjective of course, and there have been many great names in the past who have used the stroke, like Ken Rosewall - "Mister Backhand" - who made it famous long before Wawrinka was born. Wawrinka’s backhand will survive the end of his career as it will also be written into legend, but it remains to be seen if the shot will survive in contemporary tennis. Not only is it rare in the higher echelons of the game, but even more seriously, it is mostly used by players who have reached their 30s, like Wawrinka, Federer and Gasquet, or Pablo Cuevas and Feliciano Lopez.

Among the younger generation, the group is even narrower. Dominic Thiem (23) and Grigor Dimitrov (25) are almost the only exceptions and it is up to them to carry the torch. But quality transcends quantity. The one-handed backhand is rare, but when brandished by players who are just that themselves, it surely has a future. This exquisite beast is on the endangered species list, but it will survive. Patrick Mouratoglou is convinced, anyway. "Tennis is beholden to fashion so much that I do not doubt the one-handed backhand has a future. It will always be less widespread than the two-handed backhand among young people because it requires less physical strength. But I think it can grow to represent 25% of the top 100, especially if Thiem and Dimitrov are able to break into the highest level."

Their time may come. Wawrinka’s is now and with three Grand Slam titles in the age of the Big Four he has shattered his own glass ceiling. For this, he owes a big debt to the shot for which he is, more than ever, a protector, exemplar and standard-bearer.

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