Arthur Rinderknech collapsed on court in sweltering conditions before retiring from his Cincinnati Open third-round match with Felix Auger-Aliassime.
Rinderknech lost the first set 7-6 (7-4) but was level at 2-2 in the second before collapsing near the baseline as Canada’s Auger-Aliassime prepared to serve.
Auger-Aliassime and the umpire ran over to check on the Frenchman, before medical staff arrived on court.
The 30-year-old, who had been playing for nearly two hours, had a cooling break with ice packs on his neck and legs before declaring he was able to continue.
However, he lasted just two more games before retiring to send Auger-Aliassime through to the last 16.
Players have been struggling with the heat during the tournament, with temperatures regularly exceeding 30C.
British number two Cameron Norrie looked unwell and was often drenched in sweat during his second-round loss to veteran Roberto Bautista Agut on Sunday.
Wimbledon experienced its hottest opening day in June, with temperatures reaching 32.3C. Carlos Alcaraz’s five-set first-round win over Fabio Fognini was completed following a 15-minute pause in the deciding set, when a spectator sitting in the sun was taken ill.
January’s Australian Open also had sweltering temperatures approaching 34C.
Organisers introduced the Australian Open Heat Stress Scale in 2019 to monitor conditions and minimise risk to players’ health.