2018 ATP Tour Finals: Zverev def. Djokovic, Nadal, Federer on Top ranking list.

Alexander Zverev stunned world number one Novak Djokovic in straight sets to win the season-ending ATP Finals and earn the biggest victory of his career.

Djokovic, 31, was the heavy favorite to win a sixth finals title but was outclassed 6-4 6-3 by the German.

Zverev, the third seed, broke Djokovic for a 5-4 lead in the first set, then served three big aces to take the set.

The 21-year-old continued to dominate in the second and sealed a memorable victory as Djokovic faltered.

He had lost to Djokovic in straight sets in the round-robin stage but, after beating Roger Federer in Saturday's semi-finals, produced a more confident performance to stop the Serb equalling Federer's haul of end-of-season titles.

2018 ATP Finals stats, Facts.

Zverev is the first player to beat both Djokovic and Federer in the same ATP Finals
He is also the first to beat the top two seeds in the semi-finals and final of the event since Andre Agassi in 1990
Zverev, aged 21 years and six months, is the youngest champion at the ATP Finals since Djokovic in 2008
Zverev is the first German winner since Boris Becker in 1995

Mike Bryan and Jack Sock won the doubles title in thrilling fashion, coming from a set down to beat French pair Pierre-Hugues Herbert and Nicolas Mahut 5-7 6-1 13-11.

ATP World Tour finals: 2018 Ranking- players Standing.

ATP Top 20 tennis rankings list:

1. Novak Djokovic (SRB) 9045

2. Rafael Nadal (ESP) 7480

3. Roger Federer (SUI) 6420

4. Alexander Zverev (GER) 6385

5. Juan Martin del Potro (ARG) 5300

6. Kevin Anderson (RSA) 4710

7. Marin Cilic (CRO) 4250

8. Dominic Thiem (AUT) 4095

9. Kei Nishikori (JPN) 3590

10. John Isner (USA) 3155

11. Karen Khachanov (RUS) 2835

12. Borna Coric (CRO) 2480

13. Fabio Fognini (ITA) 2315

14. Kyle Edmund (GBR) 2150

15. Stefanos Tsitsipas (GRE) 2095

16. Daniil Medvedev (RUS) 1977

17. Diego Schwartzman (ARG) 1880

18. Milos Raonic (CAN) 1855

19. Grigor Dimitrov (BUL) 1835

20. Marco Cecchinato (ITA) 1819

ATP Finals 2018 Tour Results.

Day 1: Kevin Anderson beat Dominic Thiem ( Nov. 11): 6-3, 7-6

Day 1: Kei Nishikori beat Roger Federer (Nov. 12): 7-6, 6-3

Day 2: Alexander Zverev beat Marin Cilic (Nov. 12): 7-6, 7-6

Day 2: Novak Djokovic beat John Isner (Nov. 13): 6-4, 6-3

Day 3: Kevin Anderson beat Kei Nishikori (Nov. 13): 6-0, 6-1

Day 3: Roger Federer beat Dominic Thiem (Nov. 14): 6-2, 6 - 3.

Day 4: Novak Djokovic beat Alexander Zverev (Nov. 14): 6-4, 6-1.

Day 4: Marin Cilic beat John Isner (Nov. 15): 6-7, 6-3, 6-4.

Day 5: Dominic Thiem beat Kei Nishikori (Nov.15): 6-1, 6-4.

Day 5: Roger Federer beat Kevin Anderson (Nov. 16): 6-4, 6-3

Day 6: Alexander Zverev beat John Isner (November 16): 7-6, 6-3

Day 6: Novak Djokovic beat Marin Cilic (November 17): 7-6, 6-2

Nitto ATP Finals 2018 Semi-Final Line-up Complete.

Day 7: Roger Federer beat by Alexander Zverev (Nov. 17): 5-7, 6-7.

Day 7: Novak Djokovic beat M. Cilic (Nov. 17): 7-6, 6-2

Day 8: Novak Djokovic beat Kevin Anderson (Nov. 18): 6-2, 6-2.

ATP World Tour Finals 2018 winner.

Novak Djokovic beat by Alexander Zverev -- 4-6, 3-6