Daniil Medvedev told chair umpire Carlos Ramos: “I can finish the match but I can die!”
Even from the first set I didn't feel good enough with my breathing. That’s why I called the physio - I felt like my diaphragm was blocked Daniil Medvedev
The Russian Olympic Committee second seed’s dramatic outburst came as he struggled in 30-degree temperatures before defeating Italian Fabio Fognini 6-2 3-6 6-2 to reach the Olympic quarter-finals along with favourite Novak Djokovic.
The world No.2 took a medical timeout on court and called the trainer.
When Ramos asked how he was feeling, 25-year-old Medvedev said: “I’m fine. If I die, will the ITF [governing body the International Tennis Federation] take responsibility?”
Medvedev and Djokovic have advised organisers to schedule matches for cooler times in the day.
The ITF have said: “Player health is paramount”. And re-iterated their rule that players can take a ten-minute break before a third set.
Medvedev said: “Even from the first set I didn’t feel good enough with my breathing. That’s why I called the physio – I felt like my diaphragm was blocked.
“And then on the second set, I just had darkness in my eyes, like between every point. I didn’t know what to do to feel better. Like I was bending over and I couldn’t get my breath together, so I was ready to just fall down on the court.”
Australian Open finalist Medvedev meets Spaniard Pablo Carreno Busta, who scored a 7-6 (7) 6-3 win against German Dominik Koepfer.
Djokovic, on track to become the first male to secure the Golden Slam of four majors and the Olympics in the same year, defeated Spaniard Alejandro Davidovich Fokina 6-3 6-1 later in the day.
The Serb, 34, will take on lone surviving home ace Kei Nishikori, the 2016 bronze medallist who beat Ilya Ivashka of Belarus 7-6(7) 6-0.
German Alexander Zverev defeated Georgian Nikoloz Basilashvili 6-4 7-6(5) to seal a last-eight clash with France’s Jeremy Chardy, conqueror of Liam Broady, who was the last Brit standing at the tournament.
Greece’s Stefanos Tsitsipas lost to Ugo Humbert of France 2-6 7-6(4) 6-2 following a heavy fall during the second set tie-break. Humbert faces ROC’s Karen Khachanov who overcame Argentine Diego Schwartzman 6-1 2-6 6-1.