Seven-time Dubai Duty Free Tennis Championships winner Roger Federer has been drawn with Novak Djokovic at the ATP Finals tournament.
Meanwhile, world number one Rafael Nadal is in the same group with Daniil Medvedev, who he'll play at next month's Mubadala World Tennis Championships in Abu Dhabi.
Stefanos Tsitsipas and Alexander Zverev are also in their group.
The season finale gets underway on Sunday at London's O2 Arena.

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