World number four Daniil Medvedev trounced veteran Rafael Nadal 3-6, 7-6 (7-4), 6-3 to reach the grand finale of ATP Finals.
The Russian, who has won nine consecutive matches in 2020, will play Dominic Thiem for the title.
Notably, Thiem booked a spot in the championship clash by beating world number one Novak Djokovic 7-5, 6-7 (10-12), 7-6 (7-5), on Saturday.
Here is more.
As has been the case with Thiem and Djokovic of late, each set came down to dramatic finishes in the match.
However, it was Thiem who win six consecutive points from 0/4 in the final-set tie-break and converted his sixth match point.
In the other semi-final, Medvedev rallied from behind to win the second-set tie-break and then clinched the final set.
Thiem is only the second player in 2020 to win a tie-break against world number one Djokovic, who entered the third-set tie-break with a 15-1 record this season. Prior to this, he only lost a tie-break against Kyle Edmund at the US Open.
Thiem has become the first player in four years to reach back-to-back championship matches at the ATP Finals.
Djokovic was the last player to reach consecutive finals at the season finale (2012-16).
Interestingly, this was Thiem's 300th tour-level victory.
He is now the only player besides Andy Murray to beat each member of the Big Three on five or more occasions.
A year ago, Daniil Medvedev finished his ATP Finals campaign sans a single win.
Now, the world number four could become the undefeated champion this time.
Presently, he carries a streak of nine consecutive wins in 2020.
This was his first ATP head-to-head victory against Nadal (1-3).
Medvedev joins Thiem in defeating both Nadal and Djokovic in the same year at the ATP Finals.
The two heavyweights, Thiem and Medvedev, will lock horns in the ATP Finals summit clash on Sunday.
Notably, the event will crown its sixth different champion in as many years.
This has happened only once in the tournament's history (1974-1979).
The likes of Djokovic (2015), Murray (2016), Grigor Dimitrov (2017), Alexander Zverev (2018), and Stefanos Tsitsipas (2019) have been the previous champions.
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