Novak Djokovic defeats Rafael Nadal in straight sets to win ATP World Tour Finals at London's O2 Arena The Spaniard must have felt that it was his only option; as soon as the point started in earnest, Djokovic worked him mercilessly from side to side until his resistance broke. But it was a case of live by the serve, die by the serve, as a rash of double-faults helped Djokovic to two early breaks. There was a touch of suspense at the end, as a desperate Nadal managed to save two match points, the second one with a running backhand pass. But it was only a matter of time as Djokovic kept pounding away. You could see why he has won 22 matches on the bounce, and 10 in a row on this court against the best in the world. These two players have faced each other 39 times, making this the most prolific rivalry in the open era, and the pendulum keeps swinging back and forth between the pair. Starting in his glorious year of 2011, Djokovic put seven successive victories together, only for Nadal to hit back with a similar sequence over the last 18 months. Monday night's edition was not a classic, unfortunately for the 17,800 people who had crammed themselves into the O₂ Arena. Towards the end, as they realised they were not going to get a third set, a few attention-seeking idiots started shouting out feeble witticisms of the "Come on, Tim" variety. Yet while no one will be hurrying to release a DVD of the match, the one-sidedness of the result does add another twist to the narrative of these two giants of the game. We are only two months away from Djokovic's banker - the Australian Open - where he loves the slow-bouncing Plexicushion courts and has not been beaten since 2010. Then there is the Davis Cup factor to consider. Last time Djokovic and his Serbia team-mates lifted that trophy, he was inspired to put together a 41-match winning sequence, running from the start of 2011 until the semi-finals of the French Open. What could happen if he does it again? The Barclays ATP World Tour Finals may not be a grand slam, but you could see from Djokovic's pogo-bouncing celebrations that it meant a huge amount to him. There was no chink in his perfectly balanced game last night. He defended quite superbly, forcing Nadal to strain for too much in search of a rare winner. And when he got ahead early in the second set, he used his own serve tellingly to defend his lead. For Nadal, a few fallible moments at the end of a triumphant season are hardly a disgrace. He had already equalled his best finish at this tournament merely by reaching the final, and must be looking forward to the chance to put his feet, and particularly his knees, up over the next month or two. By winning his first two pool matches last week, he ensured that - no matter what miraculous results Djokovic pulls off - he will remain No 1 until after the Australian Open. But he must also know that he has gone from being the hunter to the hunted. And, as any distance runner knows, it is the man on your shoulder who usually finds the best pace. There was a tearful conclusion to the doubles event. David Marrero, of Spain, dedicated the title to his late grandfather, who died on the same day - Nov 11 - in 2011. Marrero and Fernando Verdasco had just beaten the kings of the doubles court, Bob and Mike Bryan, 7-5, 6-7, 10-7 in a hard-fought final. Verdasco said: "To win this event was unbelievably great for us, like a dream."