This is it. The final men’s tennis tournament of the 2018 season. The O2 in London will host the prestigious season-ending World Tour Finals – a Masters tournament, otherwise known as the “fifth Grand Slam,” where only the top 8 male tennis players of the year compete for the title. The best of the best are divided into two groups of four for the round-robin stages, after which the top two of each group move into the semifinals. The winner, unlike other Masters 1000 tournaments, gets a total of 1500 ATP points. Often, the year-end ranking is defined by this week in November.

Defending Champion: Grigor Dimitrov (hasn’t qualified this season)

With World no. 2 Rafael Nadal and World no. 4 Juan Martin del Potro pulling out of this edition due to injuries, let’s take a look at the eight players spread across two groups:

Group Guga Kuerten

Novak Djokovic (1)

Appearances: 11
The new World no. 1 has returned to the top of the rankings after two years, after reaching the Final of the Paris Masters last week. Djokovic was as low as rank 22 after the French Open – but he has gone on a tear after that, winning Wimbledon, Cincinnati, Shanghai and US Open. His last title in London came in 2015. If he lives up to his billing as the favourite, he will join Federer on 6 World Tour Finals titles. There is nobody more dangerous towards the end of a season. Here’s where some may argue Djokovic is greater than Nadal – the Spaniard is yet to win a title here despite all his years of qualification.
Prediction: Winner

Alexander Zverev (3)

Appearances: 2
This is only the second year the 21-year-old German has qualified in. 2017 was his breakthrough, with two Masters 1000 titles. He won at Madrid this year, too, but has again struggled on the biggest stages of the Grand Slams. Zverev, a future World no. 1, is somewhat of an enigma in that sense. He is consistently in the top 3 as far as best-of-3-sets tennis is concerned. Winning this might give him the confidence to take the leap in Melbourne in January.
Prediction: Round-Robin

Marin Cilic (5)

Appearances: 4
Cilic started the year superbly, reaching the Australian Open Final and losing to Federer. This is the fourth consecutive year he has qualified for London, but he is yet to make a mark at the tournament. Cilic hasn’t been in the best of form after the grass-court season, but his Queen’s Court title and deep runs at the first two Grand Slams have been enough to guarantee him another opportunity to upset the big guns.
Prediction: Semifinals

John Isner (8)

Appearances: 1
The tall, lanky American has finally made it to London late in his career, with a bit of luck. The ‘lucky qualifier,’ thanks to Nadal’s absence, was ninth in the ATP race. But Isner deserves his spot. His season includes a first ATP Masters 1000 title – at Miami – and an epic Wimbledon semifinal against Kevin Anderson. Isner has consistently been a threat on the quicker courts this year, and he has been rewarded with a rare spot for an American in the post-Roddick era.
Prediction: Round-Robin

Group Lleyton Hewitt

Roger Federer (2)

Appearances: 15
The Swiss master hasn’t won a season-ending title since 2011. But his six titles remains a record, and after his impressive showing against Djokovic at Paris last week, he seems to be in the mood to add to the tally. He was upset by David Goffin in last year’s semifinals despite being the favourite. He will desperately want to win a Masters title this year after winning 1 Grand Slam and 3 ATP 500 titles. He has the easier draw, and the money is on a Federer-Djokovic Final. There’s also the small matter of winning his 100th singles career title.
Prediction: Final

Kevin Anderson (4)

Appearances: 1
The 32-year-old South African is making his World Tour Finals debut after enjoying a very impressive season – where he made it to the Wimbledon Final and won an ATP 250 and his first ATP 500 title. His victory over Federer at Wimbledon after being two sets down is one of the best tennis matches of 2018. He has lost two Grand Slam finals (Nadal at US Open 2017, Djokovic at Wimbledon 2018) in two seasons, and he is getting closer to decorating his career second-wind with some prestigious silverware.
Prediction: Semifinals

Dominic Thiem (6)

Appearances: 2
Thiem couldn’t make an impact in his maiden appearance in London last year, but he has proved this season that he is more than just a clay-court specialist. His French Open Final run aside, he has impressed on the North American hard-courts, but still lacks the consistency in best-of-3 tennis. Yet, his Grand Slam performances have been good, in contrast to rival Zverev. He is a dark horse here.
Prediction: Round-Robin

Kei Nishikori (7)

Appearances: 4
Nishikori has suffered with injuries for most of last season, and he started 2018 by playing in lowly Challenger tournaments. And yet, here he is, getting the luck he deserves after the pullout of Del Potro. He has failed to win an ATP title since 2016, and has lost three Finals. But the last time he appeared here, he reached the Semifinals in 2016. He has lost to Federer twice in the last month, and will find it hard to get past the big servers in his group.
Prediction: Round-Robin

Prediction for 2018 Season-Ending Rankings:

1. Djokovic 2. Nadal 3. Federer 4. Del Potro 5. Anderson 6. Zverev 7. Cilic 8. Thiem 9. Nishikori 10. Isner