#1 Rafael Nadal
Rafael Nadal is currently the world number one but for how much longer?
The Spaniard now has Novak Djokovic to keep an eye out for after the Serb took over Federer's position in the second spot of the ATP rankings.
Nadal is only 215 points ahead of Djokovic and there are still a handful of tournaments left to be played in 2018.
The final tournament is the ATP World Tour Finals in London and it might determine who will end the year as world number one.
Nadal is hoping to compete at this month's Basel Open (ATP 500) and the Paris Masters (ATP 1000) in a bid to stay at the top of the rankings.
Can Nadal stay on top of the tree come the end of the season?
Who will end the year as world no. 1? Comment your predictions...
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