ATP Finals Groups Announced

We now know how the ATP Finals will be divided. Don't see a lot of trouble for the No. 1 and 2 seeds, but one never knows.

Group Guga Kuerten: 

Djokovic 

Zverev 

Cilic 

Isner 

Group Lleyton Hewitt: 

Federer 

Anderson 

Thiem 

Nishikori