Daniil Medvedev advanced to the US Open semifinals — but it was far from easy.

Battling the conditions of an extremely hot day in Flushing Meadows, Medvedev emerged victorious over his fellow compatriot Andrey Rublev with a 6-4, 6-3, 6-4 win in their quarterfinal clash.

The 2021 US Open winner trailed early in each set after early breaks from his childhood friend in Rublev. However, Medvedev eventually managed to turn the tide and come away with the victory in a match that lasted two hours and 47 minutes.

That was despite having breathing problems much like in his fourth-round encounter with Australia's Alex de Minaur with Medvedev requiring an inhaler during the second set changeover.

Rublev seemed to struggle with the conditions as well.

At one point while he was about to serve, Medvedev also gave an ominous warning to the camera.

“One player is gonna die. And they’re gonna see,” Medvedev said (via The Tennis Letter).

After the win, the Russian put cold towels on his head and asked for two bottles of cold water. In his post-match interview, he went as far as saying he struggled to see the ball at the end of the first set.

“The conditions were brutal,” Medvedev said. “The only good thing is that both players suffer. At the end of the first set I kind of couldn't see the ball anymore.”

Medvedev's complaints come after Canada's Vasek Pospisil complained last week of the ATP and WTA using heavier balls to slow the game down which is only resulting in more injuries to tennis players.

“There were discussions a few years back that the ATP/WTA wanted to ‘slow the game down' to have longer points for fans,” Pospisil tweeted. “The balls have been getting incrementally heavier and surprise surprise, it’s killing our bodies.

“Almost every player I’ve spoken to feels the same way. I’ve never seen more wrist, elbow, and shoulder injuries in the locker room. If these changes to the ball don’t start getting reversed, it’s only going to get worse. Please start listening @atptour @wtatour. Player injuries are bad for you too.”

Things won't get any easier for Daniil Medvedev as he faces the winner of the Carlos Alcaraz vs. Alexander Zverev quarterfinal matchup on Friday.

Should he emerge victorious in that encounter, he'll face the winner of the Novak Djokovic vs. Ben Shelton match in the final. Medvedev notably defeated Djokovic in the 2021 US Open final to win his first major.