On commentary for Eurosport, former American player Jim Courier sounded startled saying: “Oh my.”
The TV cameras captured Tsitsipas looking at the incident and walking back to his bench as the area of the court that was on fire was cleaned.
The incident was dealt with by security, Tsitsipas – who had just clinched the first set for Team Europe – was able to continue his match with Schwartzman once the court clean-up operation was complete where he went on to seal victory.
Speaking after his win, Tsitsipas said: “ It came out of nowhere. I’ve never had an incident like this happen on court. I hope he is alright. I wanted to make sure the court was playable. There was a big mark there, I wanted it cleared up before I proceeded.”
The incident came just hours before 20-time Grand Slam tennis champion Federer is due to appear on court for his farewell appearance in a doubles match alongside great rival Rafael Nadal as the pair face the American duo of Francis Tiafoe and Jack Sock.
Andy Murray is also scheduled to be in action in the opening match of the evening session, with his singles match against Australia’s Alex de Minaur preceding Federer’s final professional outing.
Security will be on a heightened alert following the protest, which came in the first session of the three-day event that continues over the weekend.