Roger Federer regained the world No. 1 ranking with the July 9 update following his title at the All-England Club. When one looks at the ranking points situation for the top three players, it suggests that Federer might stay on top of the rankings for a large portion of the remaining season.
Federer's current lead in the ATP rankings is quite slim. He only leads Novak Djokovic by 75 points. However, when you look at Djokovic and Federer, it is the Serb who has far more points to defend at the Cincinnati Masters, the Toronto Masters and the 2012 US Open.
Last season, Djokovic dominated those three events with a title at Flushing Meadows, a title at the Canadian Masters and a runner-up finish at Cincinnati. Due to that, he barely had any room for growth in those three events combined.
Federer, on the other hand, did not do that well at two of those three events. He went out early in Canada, he lost in the quarters in Cincy and, at the US Open, he fell in the semifinals. All totaled, Djokovic has 3600 ranking points to defend at those three events while Federer has just 1170.
Rafael Nadal, the current World No. 3, has been out of the top spot for over a year now. Currently he is 2,170 ranking points behind Federer. While the Spaniard was the runner-up at Flushing Meadows in 2011, he did not do well at the two Masters events in Canada and Cincinnati. All three events combined, he has just 1390 ranking points to defend this season.
The basic fact is that, in the next three major hard court tournaments (Canada, Cincinnati, and the US Open), Djokovic has a lot more to lose in terms of ranking points. If Nadal and Federer play well, they could easily gain a lot of points—especially in Toronto and Cincinnati.
The 2012 London Olympic games promise to have a major impact.
The winner of that event will receive 750 ranking points with the runner-up taking down 450. The other placements are all follows:
4th place: 270 (loser of the Bronze medal match)
Round of 16: 70
Round of 32: 35
First round: 5
Since the Olympics are not an annual event, no player has any points to defend at the London games.
From Djokovic's point of view, the games appear to be his best chance of overtaking Federer in the rankings in the near future. Otherwise, the Serb might have to play absolutely perfect in Canada, Cincinnati and Flushing Meadows while hoping that Federer plays well below his hard court standards.