World No. 3 Daniil Medvedev has put the US Open on notice during an irate outburst amid his quarter-final win vs. fellow Russian, Andrey Rublev. 

On another steamy hot day with temperatures in the mid-90s Fahrenheit (32 Celsius) Medvedev was better able deal with the stifling humidity and heat inside Arthur Ashe Stadium than eighth seed Rublev to make the Flushing Meadows semi-finals for the fourth time in five years.

Despite getting the victory, Medvedev was not happy about playing in such difficult conditions, the 2021 champion complaining into the camera while wiping off sweat in the third set let out his frustrations.

'One player is gonna die. And they're gonna see,' Medvedev said before powering on for a 6-4 6-3 6-4 win.

The all-Russian match lacked the buzz and drama of the all-American late night showdown between Frances Tiafoe and Ben Shelton hours earlier, but the sight of two seeds battling each other and the elements was no less riveting.

'The only good thing I see in these conditions is that both suffer,' said Medvedev. 'Usually there is not one that suffers so it's tough for both of us.

'Honestly, at the end of the first set I kind of couldn't see the ball anymore,' he said. 

'I kind of played with sensations. Just tried to go for it, tried to run, tried to catch the balls and he did the same.

'Sometimes before the points I was like "wow it seems like he cannot run anymore"... but he was there all the time and I was like "damn, when is he going to be tired?",' Medvedev added. 

'But actually we were tired all the time. So yeah, brutal conditions and super tough to win.'

He then compared competing for Russia in the Olympics as the only comparison to the conditions at Flushing Meadows. 

‘This and the Tokyo Olympic games were brutal, the only thing is that both of us suffer,’ Medvedev said of the wilting heat and humidity. ‘It was super tough to win. He never gives up but he knows I don’t either.

‘My tennis is ten out of ten now. Every match has been a hell of a fight here,’ he added before rushing off to take a cold shower.

Rublev was asked postmatch on his thoughts of Medvedev's death comments and whether he has internal concerns when in matches in such conditions. 

'I’m not even thinking about my health. These moments I’m thinking I need to fight... the sport is not easy,' he said. 

'You need to be ready for anything... the best players prove they’re ready and that’s why they’re the best. Yesterday Novak played in the same conditions.'