Novak Djokovic conceded he was just "trying to stay alive" as he overcame gruelling conditions to reach the semi-finals of the Shanghai Masters.
In recording a 6-3 7-5 victory over Zizou Bergs, 38-year-old Djokovic also extended his own record of becoming the oldest player to reach the last four of a Masters 1000 tournament - the 80th time he has done so.
The Serb, who had injury issues in the previous round, vomited during his win over Yannick Hanfmann in the third round after struggling with the severe heat.
Temperatures have reached 35C, with humidity at 80% in the daytime on China's east coast.