The O2 Arena was awash with the blue and white striped flags of Greece and celebrating fans after Stefanos Tsitsipas claimed the biggest tournament win of his tennis career.
At times,the raucous atmosphere made it feel as if the Greenwich auditorium had been transplanted to Athens for the evening.
The 21-year-old became the youngest ATP Finals champion since Lleyton Hewitt in 2001, after recovering from a first set tie-break loss to get the better of Austrian rival Dominic Thiem in three sets.
In a match lasting two hours and 35 minutes, Tsitsipas prevailed 6-7 (6-8), 6-2, 7-6 (7-4) to give his many countrymen and women in the crowd a moment to savour. It was the first time one of their own had claimed this prestigious – and lucrative – end-of-season title.
Thiem held a 4-2 lead in head-to-heads going into the match, but Tsitsipas carried the greater threat on the fast hardcourt surface, and deserved his triumph, even if Thiem had created the week’s greatest ripples by defeating both Roger Federer and Novak Djokovic in the group stage.
There was not much to choose between the two finalists in the first set, with both men forcing break points without managing to press home the advantage. In the tie-break, Thiem served out for the set after forcing his second mini-break with the score at 6-6.
The effort the 26-year-old Austrian put in to eke out a lead seem to take its toll and he quickly gave up the ghost in the second set as Tsitsipas broke twice for a 3-0 lead and wrapped up the set in less than half an hour.
When the Greek broke for a 3-1 lead in the decider, it looked like it might be decisive, but Thiem rallied to break back and take it to another tense shoot out.
This time, however, the tie-break was edged by the impressive newcomer, who only a year ago was winning the Next Gen Finals in Milan. He has firmly made a case this season to be a future Grand Slam champion.
“It’s been a rollercoaster. Holding this trophy is amazing,” said Tsipsipas, who is now world number six. “It’s a dream come true.
“I did get nervous at some points in the match but I managed to forget about how I felt and I had momentum in the tie-break, which was really tight.
“My fighting spirit and me constantly trying to push myself to do better got me there in the end.”
He added: “This has been the best year I’ve had and I want to constantly improve. Things were great this year and I beat some top-ranked players which gave me confidence. I’ve won matches in Grand Slams. I think I can do well in the Slams.”