New world number one Andy Murray has been drawn in a group with Stan Wawrinka, Kei Nishikori and Marin Cilic at the ATP World Tour Finals.
Murray has never won the prestigious competition and will be looking to retain his top spot in London after toppling Novak Djokovic at the head of the rankings.
This year, Murray lost to Nishikori in the US Open quarter-finals and Cilic in the final at Cincinnati. The Scot beat Wawrinka in the French Open semi-finals in June.
Djokovic will face Dominic Thiem in the opening match of the tournament at the O2 Arena on Sunday before encounters against Milos Raonic and Gael Monfils in the round-robin stage.
John McEnroe Group
Andy Murray (Britain) (1)
Stan Wawrinka (Switzerland) (3)
Kei Nishikori (Japan) (5)
Marin Cilic (Croatia) (7)
Ivan Lendl Group
Novak Djokovic (Serbia) (2)
Milos Raonic (Canada) (4)
Gael Monfils (France) (6)
Dominic Thiem (Austria) (9)
*Top two players from each round-robin group contest semi-finals
Djokovic has won the season-ending tournament for the last four years running and could claim back top spot in the rankings if he defends his title.
Murray, however, will remain at the summit if he can match or better Djokovic's run and he will be confident of doing so after securing his fourth consecutive title at the Paris Masters on Sunday.
"It's obviously nice for that to happen and to get to play in London being ranked one," Murray told ATP TV after the draw.
"Once you get out on the court though you're not thinking about your ranking, you're playing against the best players in the world.
"Every match is extremely tough and I'll look forward to getting out there. It's always an amazing atmosphere at the O2, we get great crowds there so it'll be good fun."
Murray's success has put him 405 points ahead of Djokovic in the rankings but has also meant an exhausting few weeks for the British number one.
"I'm trying to take a few days rest now," Murray said.
"Obviously I finished on Sunday in Paris. I'll start hitting again on Thursday. I need a few days break now and will start practising again nearer the weekend.
"It's one big final push for all the guys in the event. It's been a lot of tennis for everyone this year so hopefully everyone plays well."
Murray's greatest threat in the group stage will be Wawrinka, the world number three who won his third grand slam title at the US Open in September.
The Swiss had won three consecutive matches against Murray before their most recent meeting at Roland Garros, when the Briton came through on the clay in four sets.
"It's been amazing what he's done this year and also over the past 10 years," Wawrinka said.
"He's an amazing player, he's been fighting for everything and winning almost everything. He deserves to be number one, he's played so well recently.
"It will be good for him playing at home, being number one just now, so it will be an interesting tournament."