The Laver Cup contest between Stefanos Tsitsipas and Diego Schwartzman was halted in incredible circumstances when a protestor ran on to court and set themselves on fire.
The man in question was quickly dragged off the court before play resumed in the second match of the day. A quick check from officials concluded that no damage had been done to the playing surface.
Spectators in the crowd soon took to social media to describe how the protestor had brought a flare onto the court and tried to set his own arm alight. His t-shirt bore the slogan 'End UK Private Jets'.
Tennis reporter Uche Amako tweeted: "Dramatic scenes moments ago at the Laver Cup as a protester got onto the court, sat down and set something on fire. He was wearing a shirt which said 'End UK private jets'..."
Despite the crowd being reduced to stunned silence Oliver Brown, the Chief Sports writer for The Telegraph, said the European captain wasn't fazed: "Staggering picture from EPA 's Andy Rain of a protestor who has just his arm on fire on court here at the Laver Cup. Bjorn Borg as impassive as ever in the background."
@griffinsue639, in attendance at The O2, described how officials dealt with the bizarre incident: "Laver Cup and guy scrambles onto court and lights something [his arm] on fire. Security drags guy off with apparently no damage to the court and play resumes."
The staggering scenes came just hours before Roger Federer takes to a court for the final time in his professional career. Tickets for the opening day have sold at extortionate prices since the Swiss maestro confirmed his doubles match with Rafael Nadal would be his final bow.
Earlier in the day, Casper Ruud had given Team Europe the perfect start when he beat Jack Sock in a tie-break decider. Following the drama, Tsitsipas made it 2-0 to Borg's men by beating Schwartzman in straight sets.
Andy Murray will play Alex de Mineur in the third match, before Federer's big moment. He and long-time friend and rival Nadal will take on Sock and Frances Tiafoe.
