Measuring Up: How smaller pros are impacting an increasingly tall ATP

There is plenty to suggest that bigger is better on the ATP tour these days.

The Top 10 has never been taller, thanks to recent breakthroughs like 6'6" Alexander Zverev winning three Masters titles, 6'8" Kevin Anderson reaching two Grand Slam finals, and 6'10" John Isner winning his first Masters title at Miami and reaching his first Grand Slam semifinal at Wimbledon. Add to that the recent resurgences of Juan Martin del Potro and Marin Cilic, who at 6'6" are the tallest players ever to win Grand Slams.

The advantages of height in tennis have been amply documented—more power, more angles, more reach. Nowhere is this more apparent than while serving. The ATP statistics in this category are dominated by giants like Isner, 6'11" Ivo Karlovic, and Anderson.

Tall players have also improved their movement, traditionally an area of weakness, to become more and more relevant at the top of the game.

But even now, being tall isn't all—smaller players have also been making an impact. The most prominent is David Goffin, a generous 5'11" and No. 11 in the rankings. The Belgian was as high as No. 7 following his wins against both Rafael Nadal and Roger Federer at last year's ATP Finals, where Nadal was injured but still highly competitive.

Just one spot behind at No. 12 is Diego Schwartzman, 5'7" and the sole player to take a set off Nadal at the French Open. There's also recently injured Grand Slam finalist Kei Nishikori, Fabio Fognini and Philipp Kohlschreiber, all 5'10" and established Top 25 players or better. They have been joined by Damir Dzumhur, 5'9", who in July reached a career-high No. 23 and won the first two titles of his career in 2017.

Their prowess, by contrast, is better reflected by the ATP's return statistics. After Nadal and Novak Djokovic, you'll find Schwartzman, Dzumhur, Goffin and Fognini among the top eight in the ATP's "Return Rating," a measure of return points won against first and second serves, along with return games won and break points converted. the highest-rated players on the return are Schwartzman, Dzumhur and Goffin. Other players whose career statistics are comparable to the current leaders include David Ferrer, 5'9", and Nishikori, who is still coming back from injury.

Even historically, a lot of the game's best returners have been of then-average height or lower.

Some of this is sheer necessity. Most successful smaller players have to have a good return, as they tend to be more vulnerable when serving. Some of it is just ability.

"I think I have a good return," says Schwartzman. "Nothing about the size. A lot of taller guys have a good return.

"I practice a lot the return."

Tough Call: Would you rather be a 6’11” or 5’7” professional tennis player?

Nevertheless, smaller players do benefit from some inbuilt advantages while returning: speed and a lower strike zone. They can get to the ball while it is still on the rise, and hit it effectively at that height. Taller players have to stand further back if they want to take the ball in their own, higher, "strike zone"—the waist-shoulder level that is optimal for hitting groundstrokes.

While each approach has its pros and cons, being lower to the ground allows for more offensive returns.

"I think the speed, agility and reaction, that's why the smaller players have a better return," said Dzumhur. "I can take it [on the rise], both sides. The taller guys can take it higher so they have a better angle.

"It doesn't just depend on height but also on technique. For me, it's definitely easier when I have low ball[s]."

This can also transfer to other areas of the game. Before, smaller players used to be known for being excellent retrievers, chasing down shots way behind the baseline. But now it is common to see such players step in and hit big, especially against today's high-kicking balls.

"They can be more aggressive, in their own way," said Marcos Baghdatis, who himself is 5'10".

"I like to play this style," Goffin has told L'Equipe in French. "I find there are a lot of things you can do—get on the ball, move the other players, run around."

Schwartzman concurs. "I know I move better than them, and for [hitting] things inside the court it's helping," he said, though adding he has to work harder and counter the power of bigger opponents. "Trying to concentrate, trying to practice, trying to do everything, because I know I don't have big serving or the high speed on the forehand and on my backhand I have to run a lot, be inside the court for many hours."

But smaller players can benefit by being forced to develop their games and competitiveness, notes Dzumhur, even if it requires a lot of effort.

"Sometimes, you think, 'That 10 cm would suit you good,'" he smiles. "Definitely I am not serving 220 K.P.H. like a lot of other players, or I can't hit my forehand as hard as other players, but I can hit some different shots, hit good slices. I can mix up my game more than the tall players, in terms of speed, in terms of being active on the court.

"I have a different game than the others, so I'm trying to use all my best things against every player. It gives a lot of advantage, when other players know they have to play really long to win a point against me, when they know try have to play really good to win. It becomes very mental, and I think today's tennis is very mental because all the players are really physically prepared.

"I think the smaller players, in today's tennis, where the physical is very important, where fitness is very important, that's why we are coming up."

It remains to be seen if players of Schwartzman's stature can still reach the top of the game, but the Argentine argues it's quality that counts.

"If you play good tennis, you can beat anyone," he said.

Big words. But he and other smaller players are backing them up.

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