Djokovic drawn to face Zverev and Cilic in London
Novak Djokovic will face Alexander Zverev and Marin Cilic in the round-robin stage at the ATP Finals, while Roger Federer will get the chance to exact revenge on Kevin Anderson in London.
Five-time champion Djokovic was drawn in Group Guga Kuerten on the day he returned to the top of the rankings and Rafael Nadal withdrew from the season-ending tournament due to ankle and abdominal injuries.
The 14-time grand slam champion, guaranteed to end the year as world number one, will compete with Zverev, Cilic and debutant Josh Isner - Nadal's replacement - for a place in the semi-finals.
Djokovic's 22-match unbeaten run was ended by Karen Khachanov in the Paris Masters final on Sunday after beating Federer in a classic last-four encounter.
Federer - a six-time winner of the prestigious event - will come up against Anderson, Dominic Thiem and Kei Nishikori in Group Lleyton Hewitt.
Anderson, who will make his first appearance in the tournament at the age of 32, beat Federer in the quarter-finals at Wimbledon, taking the final set 13-11.
Nishikori was beaten by Federer in the last eight in Bercy last week before getting the call to replace the injured Juan Martin del Potro in the ATP Finals, which start at the O2 Arena on Sunday.