The 23-year-old Russian Andrey Rublev defeated world no. 3 Dominic Thiem 6-2, 7-5 in an hour and 14 minutes, earning his first ATP Finals victory. The Austrian defeated Stefanos Tsitsipas and Rafael Nadal to secure the semi-final spot, playing on a competitive level only in the second set today and dropping the last three games to propel the Russian towards the win, his 41st of the season.
Andrey lost serve once and produced four breaks from ten opportunities, hitting 26 winners and nine unforced errors to control the scoreboard and race over the top. Rublev made a strong start, dropping only three points behind the initial shot and scoring two early breaks for 6-2.
The Russian fired 11 winners and no unforced errors, hitting a service winner in 57% of all the points behind the initial shot to walk past Thiem, who was far from his usual level. Andrey forced an error from Dominic in the opening game to grab a break and held at 15 with an unreturned serve for a 2-0 lead.
Thiem suffered another break in game three following a forehand down the line winner from Rublev, falling 4-0 down after just 13 minutes when his rival hit an ace. The Austrian held at 15 in game five to add his name to the scoreboard, followed by another booming serve from the Russian, who closed the sixth game at love to move 5-1 in front.
Andrey Rublev wrapped up the breakthrough season with a win.
The US Open champion grabbed the seventh game with an ace down the T line, reducing the deficit before sending a backhand wide a few minutes later to hand the set to Andrey.
With momentum on his side, Rublev landed a forehand down the line winner in the second set's third game to clinch a break and forge the advantage, confirming it with a service winner in the next one for a 6-2, 3-1 lead.
Thiem reduced the deficit in game five, and they both served well in the next couple of games to remain within the same distance. From 40-15 up, Andrey lost four straight points on serve in game eight, netting a forehand to bring the rival back on the scoreboard.
Thiem held at 15 to move 5-4 ahead, looking good to perform a comeback and steal the set. Instead of that, Rublev held in game ten in under 50 seconds and scored a break in the next one when Thiem's volley landed long, converting the fourth break chance and serving for the victory.
The Russian landed an ace in that 12th game to seal the deal and notch his first ATP Finals victory, hoping for many more in the years to come if he continues playing like this.