“Do you want a player to die on court?”

That was the question Holger Rune asked an official as he was treated by a doctor and physio in gruelling conditions at the Shanghai Masters.

With temperatures reaching as high as 34C and humidity at 80% in the daytime at the end of a long season, players are feeling the impact physically.

Conditions are similar 500 miles west at the Wuhan Open, where Emma Raducanu retired from her first-round match on Tuesday with dizziness. On Monday, matches on the outside courts were halted and the roof on the main court closed.

After retiring with illness from a match against Sorana Cirstea on Tuesday, former French Open champion Jelena Ostapenko revealed she had “suffered a heat stroke”.

Iga Swiatek enjoyed a 6-1 6-1 rout of Marie Bouzkova, but the world number two said afterwards she was grateful not to have played on Monday, when the heat was “too much for most of the players”.

“I hope the other matches will be scheduled at a time where girls can compete, rather than just die on the court,” Swiatek added.

Back in Shanghai, Rune had his blood pressure taken and an ice towel around his shoulders after feeling unwell in his third-round win over Ugo Humbert on Sunday.

Novak Djokovic said the conditions in his gruelling third-round win were “brutal”, Giovanni Mpetshi Perricard said he felt like he was “dying on the court” because of the humidity, and Jannik Sinner could barely walk as he was hit by cramps in his Sunday night match.

Terence Atmane, who retired from his first-round match on Thursday, posted on Instagram that his on-court stress was heightened by the heat.

“After the first point of the match both of my hands were shaking,” the Frenchman wrote.

“After the second game and a comfortable 2-0 lead I immediately felt my entire body shaking and I was suffocating after every point.

“The heat stress I’ve faced today could have been worse than losing my consciousness for an hour and just rapid heartbeat…”

Rune, as he was being treated on Sunday, asked why men’s governing body the ATP has no heat rule in place.

“It’s a very good question,” was the reply.

Denmark’s Rune returned to the theme on Tuesday after a three-set win over Mpetshi Perricard in the fourth round.

The world number 11 said he thought “every player would agree” a rule should be introduced.

“We can handle a certain amount of heat, because we’re strong and mentally strong as well, but there is always a limit.

“It’s also important to take care of your health. We need to survive.”