LONDON: Novak Djokovic of Serbia defeated Rafael Nadal from Spain in straight sets to win the ATP World Tour Finals on Monday, ARY News reported on Tuesday. This was Djokovic’s 22nd consecutive win and 7thtitle of the year. Tough competition was seen between the two players in the first set. Djokovic took the first set 6-3. The Serbian, playing with his ordinary tennis, won the second set 6-4 to win the tournament.