The Barclays ATP World Tour Finals is the big finale at the end of the tennis year, and features the top eight players in the men's world rankings. No women take part.
The format for the competition is a mix of group stages followed by knockout rounds. The first six days are split between two groups of four, with the top two players from each group contesting the semi-finals. The ultimate winner is awarded 1,500 rankings points.
Note: Each session begins with one doubles match, followed approximately two hours later by one singles match (depending on how long the doubles match takes). The players for each session are only announced 24-48 hours before each session begins.
Last year's competition saw Andy Murray defeat Novak Djokovic in the final, to capture his first ever season-ending crown.
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