Britain's Andy Murray has been drawn in the same group as Roger Federer for the ATP World Tour Finals in London.
Murray, 27, has won three titles in the past six weeks to qualify for the eight-man season-ending tournament, which takes place from 9-16 November.
The Scot is in Group B along with Swiss second seed Federer, Japan's Kei Nishikori and Milos Raonic of Canada.
Top seed Novak Djokovic, Switzerland's Stan Wawrinka, Czech Tomas Berdych and Marin Cilic of Croatia are in Group A.
Murray will open play at the O2 at 14:00 GMT on Sunday against Nishikori, followed by Federer against Raonic at 20:00.
Wawrinka and Berdych begin proceedings on Monday, with Djokovic and Cilic in the evening session.
The top two players in each group will progress to the semi-finals, with the standings based initially on match wins, although it can come down to the percentage of games won or even world rankings as the final tie-breaker.
Murray has avoided defending champion Djokovic, who beat him at the Paris Masters last week to end his 11-match winning run.
But the 2013 Wimbledon champion will face Federer, who is attempting to regain the world number one spot and win this title for a seventh time.