|2019 Nitto ATP Finals|
|Venue: O2 Arena, London Dates: 10-17 November|
|Coverage: Watch live coverage of one match per day on BBC TV, BBC iPlayer and online; Listen on BBC Radio 5 Live Sports Extra; Live text on selected matches on the BBC Sport website and app. Click here for Live Guide.|
Sixth seed Stefanos Tsitsipas won his opening match at the ATP Finals by edging out fourth seed and fellow debutant Daniil Medvedev in London.
Tsitsipas had lost all five of his previous meetings with US Open runner-up Medvedev and the pair have had a difficult relationship since a row over a net cord in Miami last year.
Tsitsipas then called the Russian’s playing style “boring” after a defeat at the Shanghai Masters last month.
The pair are two of the most highly-rated young players in the game – two of four singles players aged 24 or under at this year’s championships – but Tsitsipas was rewarded for being the more aggressive of the two players.
Asked whether beating Medvedev meant extra to him, the Greek said: “It means more than extra.
“It’s a victory that I’ve craved for a long time now and it’s great that it came in this moment.
“Our chemistry definitely isn’t the best that you can find on the tour. It just happens with people that it’s not that you can just like everyone.
“It’s not that I hate him. I guess, as he said, we will not go to dinner together.”
There were no breaks in the first set but Tsitsipas played better in the tie-break, earning the crucial mini-break to move 6-5 ahead by winning a gruelling point at the net with a volley.
The second set was similarly tight but Tsitsipas remained immaculate on serve – he did not face a break point in the match – and eventually broke serve to go 5-4 in front, helped by the Russian choosing not to volley a return at 30-30 that landed in.
Tsitsipas served out the match in the following game, and celebrated enthusiastically after the final point as he moved top of the early group table.
Tsitsipas, who beat Federer en route to the semi-finals of this year’s Australian Open, won the Next Gen event a year ago – the season-ending tournament for players aged 21 or under.
He said he had “goosebumps” when making his debut in London.
“I watched this event for the first time in 2010, I used to watch on TV dreaming of potentially playing on these courts,” he said.