Wawrinka wilts against Djokovic in London Serbian Novak Djokovic moved within touching distance of ending the year as the world number one after crushing Switzerland's Stan Wawrinka 6-3, 6-0 at the ATP Tour Finals tennis tourney on Wednesday night. Djokovic needs to win all three of his Group A matches to ensure he will hold off Roger Federer in the race for first place. He secured the second of those victories with a ruthless 65-minute rout at London's O2 Arena. The reigning Wimbledon champion will be guaranteed top spot if he beats Tomas Berdych on Friday in a match he also has to win to be certain of making the last four at the prestigious season-ending event. Wawrinka's loss means the Swiss world number four needs to defeat US Open winner Marin Cilic, thrashed 6-3, 6-1 by Berdych earlier on Wednesday, to have a chance of making the last four.