Rafael Nadal and Novak Djokovic will go head-to-head once again in the ATP World Tour Finals

Nadal beat Roger Federer in  7-5 6-3 where Djokovic beat Stanislas Wawrinka in 6-3 6-3 in semifinals. 
Nadal currently World No 1 will face Djokovic, current World no 2 in London.