With 13,845 points, Serbian star Novak Djokovic held on for the 144th week the top spot in the Association of Tennis Professionals (ATP) singles rankings issued on Monday.Swiss Roger Federer placed a distant second with 8,385 points, followed by Scotsman Andy Murray and Spaniard Rafael Nadal, reports Efe.Meanwhile, Swiss Stanislas Wawrinka jumped to the ninth place with 3,495 points, upsetting Croat Marin Cilic. The current ATP ranking and point scores are as follows:1. Novak Djokovic (Serbia) 13,845 points2. Roger Federer (Switzerland) 8,3853. Andy Murray (Scotland) 6,060 4. Rafael Nadal (Spain) 5,3905. Kei Nishikori (Japan) 5,2806. Milos Raonic (Canada) 5,0707. Tomas Berdych (Czech) 4,9608. David Ferrer (Spain) 4,490 9. Stan Wawrinka (Switzerland) 3,49510. Marin Cilic (Croatia) 3,405.