Novak Djokovic claimed first place in Group A with his 6-2, 6-2 victory over Tomas Berdych this afternoon in London, but there is still lots to play for the group’s other two members.

Read: Djokovic Claims ATP's Year-End No. 1 Ranking

Per the ATP, here are the qualification scenarios for Group A. The final match of round-robin play will be played this evening between Marin Cilic and Stan Wawrinka. Basically, Cilic needs to win in straight sets to have a chance:

1) Regardless of score, if DJOKOVIC defeats BERDYCH and WAWRINKA defeats CILIC, then DJOKOVIC wins the group and WAWRINKA qualifies 2nd.

2) If DJOKOVIC defeats BERDYCH in 2 sets and CILIC defeats WAWRINKA in 3 sets, then DJOKOVIC wins the group and WAWRINKA qualifies 2nd.

3) If DJOKOVIC defeats BERDYCH in 2 sets and CILIC defeats WAWRINKA in 2 sets, then N. DJOKOVIC wins the group and order of remaining players is determined by % of games won.