Commenting for Eurosport, former American player Jim Courier sounded shocked and said: “Oh my.”
The TV cameras captured Tsitsipas watching the incident and walking back to his couch while the area of the court that was on fire was being cleaned.
The incident was handled by security, Tsitsipas – who had just won the first set for Team Europe – was able to continue his match with Schwartzman after the clean-up of the field was completed, where he sealed the win.
After his win, Tsitsipas said: “It came out of nowhere. I’ve never seen an incident like this in court. I hope he’s okay. I wanted to make sure the field was playable. There was a big mark there, I wanted it cleared up before I continued.”
The incident took place just hours before 20-time Grand Slam tennis champion Federer will appear on court for his farewell doubles appearance alongside great rival Rafael Nadal as the pair face American duo Francis Tiafoe and Jack Sock.
Andy Murray will also be in action in the opening game of the evening session, with his singles match against Australian Alex de Minaur ahead of Federer’s final professional appearance.
Security will be extra vigilant following the protest, which took place during the first session of the three-day event that continues this weekend.