Adam Walton has notched the biggest scalp of his grand slam career when stunning former world No.1 Daniil Medvedev with a superb performance at Roland Garros, pulling off a massive comeback in the deciding set.

The Queenslander, who is currently ranked 97, revelled in the heat against the former US Open champion and sixth seed to progress 6-2 1-6 6-1 1-6 6-4 in a 3hr 22min match of swinging momentum on Court Suzanne Lenglen.

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The first four sets of the opening round match were lopsided and the fifth looked to be heading the same way when Medvedev, who received a pep talk from his wife Daria in the infancy of the match, broke the Australian early.

But Walton, who received the Tennis Australia wildcard into the French Open, rallied strongly from 2-4 down to level and then survived a testing service game of his own at 4-all, in which he saved two break points, to edge ahead.

In a remarkable finale, the 27-year-old was able to break the frazzled Medvedev, who was described as playing better than ever just two days earlier by Novak Djokovic, to love to clinch the biggest win of his career.

On posting his triumph on the famous stadium court, Walton put his hands to his head in disbelief and, after shaking hands with his rival, rushed to his supporters courtside to celebrate.

He later said his ability to hold serve when trailing 1-3 in the fifth set when saving a string of break points proved critical to his ability to stay in the match.

Australia’s Adam Walton reacts after a point as he plays against Daniil Medvedev during their men’s singles match on day 3 of the French Open tennis tournament on Court Suzanne-Lenglen at the Roland-Garros Complex in Paris on May 26, 2026. (Photo by Thomas SAMSON / AFP)Source: AFP

“He was playing pretty well (and) making a lot of first serves, and he was liking my ball, but I knew I just had to hang tough,” Walton said.

“I thought the 3-1 game, I faced some break points there, and if I go down 4-1 it is a double-break it’s going to be pretty tough from there. So getting that hold and definitely just keeping the score close (was important). I knew if I just kept fighting, maybe, maybe I would get a chance and … I’m glad I did.”

Pitted against one of the world’s leading defenders, Walton produced a well-balanced match, with his all-court game and exceptional movement frustrating the mercurial Medvedev, whose frustration bubbled over on occasion.

Midway through a first set dominated by the Australian, Medvedev began complaining about the heat, but his wife Daria was having none of it, telling the 2021 US Open winner it was the same for everyone.

Although the temperature of 32C may not sound extreme by Aussie standards, those in attendance from Melbourne in Victoria to Melbourne in Florida and everywhere in between found it stifling.

It prompted Paris officials to issue a severe heat warning, though Walton was more than happy with the sizzling temperature.

And he had the benefit of belief, having previously edged the Russian star in the Cincinnati Masters last year.

“It’s definitely hotter than previous years that I’ve played here, but … we grow up in the heat, we like the heat,” he said.

“It makes the ball move faster through the air, which I think helped my game today. So I really like it when it’s hot in Paris.”

Daniil Medvedev of Russia reacts as he plays against Adam Walton of Australia during their first round men’s singles tennis match at the French Open tennis tournament in Paris, Tuesday, May 26, 2026. (AP Photo/Aurelien Morissard)Source: AP

His reward is a clash with American Zach Svadja, who ousted Walton’s compatriot Alexei Popyrin 6-3 3-6 7-6 (3) 7-5.

The Australian, a former Roland Garros boys champion, will lament a string of missed opportunities as the match tightened, which included an errant drop shot when serving to force a deciding set.