Just as 6’8”, 265-pound basketball superstar Lebron James could never be a horse racing jockey, whose weight averages 108 to 118 pounds, former junior Wimbledon champion Noah Rubin conceded he was too short to make it on the ATP Tour. So the 5’9”, journeyman Rubin, whose ranking peaked at just No. 125 in 2018, recently quit tennis and announced he was switching to pickleball. In a video on Instagram, the 26-year-old American said, “The tennis court is just way too big and there’s way too much ground to cover.”

Just as 6’8”, 265-pound basketball superstar Lebron James could never be a horse racing jockey, whose weight averages 108 to 118 pounds, former junior Wimbledon champion Noah Rubin conceded he was too short to make it on the ATP Tour. So the 5’9”, journeyman Rubin, whose ranking peaked at just No. 125 in 2018, recently quit tennis and announced he was switching to pickleball. In a video on Instagram, the 26-year-old American said, “The tennis court is just way too big and there’s way too much ground to cover.”

The last men’s Grand Slam singles champion under 6’ tall was 5’9” Gaston Gaudio, a longshot who shocked everyone, including himself, by winning the 2004 French Open. This decade, 5’7” Diego Schwartzman has defied considerable odds. The 30-year-old Argentine reached the French Open semifinals in 2020 when he ranked a career-high No. 8. Much like Michael Chang, who grabbed the 1989 French Open in another shocker and ranked a career-high No. 2, Schwartzman boasts excellent groundstrokes that generate plenty of power, top-notch speed, and great competitiveness. Even so, it’s highly unlikely he’ll ever win a major title.

It’s a truism in sports that “the good big man beats the good small man,” and that holds true more than ever in pro tennis today. The average height in the men’s top 100 has increased to about 6’3.” While Rubin’s small stature prevents him from belting big serves, reaching some passing shots, and handling high-bouncing balls, today’s tennis big men are faster and more athletic and agile than ever. Daniil Medvedev, a wiry, 6’6” Russian who captured the 2021 US Open, exemplifies these assets, just as 6’1” Venus Williams did 20 years ago.

Tellingly, the three greatest players in men’s tennis history aren’t giants. Rafael Nadal and Roger Federer are 6’1” and Novak Djokovic is 6’2”. Teen phenom Carlos Alcaraz, the US Open champion and new No. 1, is listed at 6’1” but may be slightly shorter.

Alcaraz has compensated for his relative lack of height with tremendous strength, just as husky, 6' Stan Wawrinka, a three-time major winner, has. The muscular, 180-pound Spaniard can belt serves over 130 mph and forehands over 100 mph. Best of all, Alcaraz uses his explosive running speed both offensively and defensively, and he blends power with touch better than any previous champion. In short, the hyper-athletic Alcaraz is the 2020s exception that tests the rule that taller is better.

Does that mean the proverbial “little guy” is doomed in pro tennis?

I cannot foresee how a sub-6-footer can win a Grand Slam title or an Olympic gold medal. He can certainly rank in the bottom half of the top 10, particularly if he excels on clay. By 2030, though, even that may not be possible simply because players from 6 feet to 7 feet tall (Reilly Opelka is a quarter inch below that) are so much more prevalent in the population, and they are much better athletes than ever before.

Can women 5’6” and shorter still win majors? Ashleigh Barty, a solidly built 5’5”, proved they can—even with a mediocre backhand. Barty impressively won her three Grand Slam titles on grass, clay, and hard courts. But the undersized Aussie was a terrific athlete with an outstanding volley and a serve that produced plenty of aces. She also was fast and tactically smart. In other words, she was a rare exception to the rule that taller is better.

More than ever before, however, bigger is better in tennis. Thirty years ago, Arthur Ashe commented that the court is just too big for women. Now I believe the court is too small for the towering men on the pro tour.

In my award-winning instruction book, The Fein Points of Tennis: Technique and Tactics to Unleash Your Talent, I discuss the best tactics for players of all heights.