Daniil Medvedev defeated fellow Russian Andrey Rublev 6-4, 6-3, 6-4 in scorching conditions Wednesday to reach his fourth US Open semi-final and set up a possible meeting with defending champion Carlos Alcaraz.
Third seed and 2021 champion Medvedev rallied from a break down in all three sets as he condemned a frustrated Rublev to a ninth straight Grand Slam quarter-final loss.
Medvedev will play Alcaraz or German 12th seed Alexander Zverev for a place in Sunday's final after an energy-sapping duel against the eighth-ranked Rublev as the temperature hit 95 degrees Fahrenheit (35 degrees Celsius) in New York.
At one point during the third set Medvedev muttered to a nearby TV camera "one player is going to die and they're going to see" as he grabbed a towel mid-game.
"The conditions were brutal. The only good thing is that both players suffer, so it's tough for both of us," Medvedev said after the 2hr 48min encounter, during which the extreme heat policy was in effect.
However, it only applies at the conclusion of the third set in the men's tournament when players are allowed to leave the court for 10 minutes.
"At the end of the first set I kind of couldn't see the ball anymore. I kind of just played with sensations," added Medvedev.
Medvedev arrived at his post-match press conference with visible red blotches on his face, the result he said of towelling down regularly after points.
"Because we are sweating so much and use a lot of towels, I have no skin left on my nose, and here it's red, but it's not because of the sun so it's not like you're burned but I have no skin left.
"I just saw Andrey in the locker room and his face very red, and it's also not because of the sun so I guess it's the same. That tells everything, like we left everything out there."
- 'Not thinking about health' -
Rublev accepted the roasting heat and humidity were uncontrollable factors and part of the challenge.
"I'm not even thinking about my health," he said.
"At this moment, these moments I'm thinking that, I don't know, I need to fight. Doesn't matter how is tough. I mean, the sport is not easy. And you need to be ready for everything that can happen."
Medvedev overturned a 3-0 defeat in the opening set against Rublev, the godfather of his infant daughter, in a repeat of their 2020 quarter-final.
He dropped serve twice in the second set but hit back for a 4-3 lead before summoning the trainer complaining of breathing difficulties.
Medvedev resisted three break points the very next game and broke once more to claim a two-set lead.
Both players repeatedly placed towels packed with ice around their necks at changeovers, hunching over at times after draining rallies, while Medvedev took puffs from an inhaler.
Rublev twice surged in front in the third set only for Medvedev to respond on both occasions, sealing victory in a marathon final game courtesy of his nine break of the match.
"I know he never gives up. The thing is he knows I never (give up) too," said Medvedev.
"A few moments in the third set he was up a break.
"I couldn't wait to go to the cold shower, but the thing about that is when you come out either you can't move because your body blocks or you feel better.
"I just thought I don't care, I'm just going to do it, but I didn't need to, so I am going to do it now."