Djokovic who won the title four years in a row between 2012-2015 has had another stellar year winning five titles, i.e. the Australian Open, Wimbledon, Madrid Masters, Paris Masters and the Tokyo ATP 500.
The Spaniard suffered an abdominal problem at the Paris Masters last week and had to pull out prior to his scheduled semi-final against Denis Shapovalov, prompting concerns he may again miss the season-ending showpiece.
The players play three round-robin matches with the top two in each group progressing to the semi-finals.
The ATP Finals Draw took place today - eventually - and when they did, Novak Djokovic and Roger Federer were paired together in Group Bjorn Borg.More news: Pokemon Sword & Shield English Overview trailer
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The other group boosts of World No. 1 Rafael Nadal, Daniil Medvedev, Stefanos Tsitsipas and Alexander Zverev.
As a six-time former champion of the event, he will play five-time victor Djokovic for the 49th time in the round-robin group stage. Zverev is the defending Champion.
Djokovic will also finish the year as No 1 if he wins the tournament and Nadal does not reach the semifinals. The two Serbians enjoyed the view of a few oranges as well during their train trip, as it can be depicted from one of the latest Instagram posts of Novak. With a lot of unpredictability and uncertainty to look forward to, a tennis fan will be delighted as that is precisely what would make for a phenomenal end to another spectacular year on the ATP calendar.