London - Novak Djokovic's tremendous run of form since the start of the year means the Serb has already booked his spot at the ATP World Tour finals in London.
The 23-year-old emulated the feat of Rafael Nadal in 2009 by guaranteeing a place in the eight-man showpiece before the French Open, the ATP Tour said on Monday.
Djokovic took his winning streak to 37 matches with a straight-sets defeat of Nadal in the Rome Masters on Sunday, his seventh title of 2011.
It is the fifth season in a row that Djokovic has qualified for the end-of-year finals which will be staged in London for the third time in November.
Australian Open champion Djokovic is now just 405 points behind world number one Nadal in the rankings and could reach the summit for the first time in his career at the French Open which starts on Sunday.