A former top-20 player has named which ATP star is arguably the “toughest” in men’s tennis.

In years to come, the 2026 season may be seen as the one when everyone got injured. Carlos Alcaraz missed four months of the campaign with a wrist problem, and Jannik Sinner won’t play again this year due to a knee issue after winning the Wimbledon title in mid-July.

Novak Djokovic has had a number of health and physical concerns; Arthur Fils has missed sizeable chunks of the year, as have Lorenzo Musetti, Casper Ruud, Joao Fonseca, Taylor Fritz and more.

Sinner has the best win/loss record at 44-3, followed by Alcaraz at 32-4, and then Alexander Zverev at 59-15. The German leads the way when it comes to Tour wins this season, which have included maiden Grand Slam wins at the French Open and US Open.

While his rivals have fallen by the wayside, the 29-year-old has powered through. He looks set to be rewarded for his efforts, in combination with Sinner’s injury woes, as the No 1 ranking is on the tip of his fingers.

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Barring a catastrophic end to the season, Zverev will be the 20th year-end No 1 in men’s tennis history. That, and more, is why former world No 14 Jan-Michael Gambill thinks he is the sport’s iron man right now.

The 6ft 6in player, who has been likened to Taylor Fritz, did lose a three-set epic to Djokovic at the China Open last week but that should not take away from his marathon-man-like status.

When asked if Zverev needs a rest period after a gruelling stretch, Gambill said on the Inside-In podcast, “I mean, why would you stop? What he’s been working so hard for has finally coalesced in front of him this year. He makes three Grand Slam finals before he finally makes a breakthrough and wins his first, and now a second slam, and he didn’t look back. Why stop?

“I mean, he’s in incredible shape physically. He’s got no injuries right now. The end of the year can be a bit of a drag, but I don’t think it’s a bit of a drag if you just won the US Open and the French Open. That’s exciting. So he’s got to ride that high. And frankly, I think he just loves tennis, doesn’t he? He wants to be on the tennis court.

“He reminds me a little bit of like how Taylor Fritz. Taylor Fritz just loves tennis, wants to play tennis, wants to play tennis tournaments, wants to play Davis Cup, continue to be involved, have those eyes on him. It gets to be a little bit of an addictive thing whe you’re winning and the things are really going your way.

“He doesn’t play with a lot of flash and he’s still one of the toughest out in tennis right now. You just you just have to find a way to beat him. You have to power through him and only a couple of guys have that ability.”

Former Wimbledon quarter-finalist Gambill also likes how Zverev is able to “win ugly” and just goes about his business week-in, week-out. That was certainly the case in the first two rounds of his US Open triumph, where he was taken to five sets by Lorenzo Sonego and Quentin Halys.

The American added, “He didn’t even play well at the beginning of the US Open. He was playing terrible. Two points away [from going out in round one]. Those two first two matches [at the US Open] wasn’t good tennis. He was tentative on his forehand. But the guy still has this will in his brain that he just pushes through these situations where some guys would be out of that event.

“Sometimes we get even tighter and getting more nervous. He just finds a way to win these matches. And it’s like back to Brad Gilbert’s Winning Ugly. Some of those matches were ugly and you want them, you know, that Grand Slam champ again, two times over this year. That’s amazing.”

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