[[Ed. note: Rosangel, Tennisworld's Mistress of the Numerical Arts, has been at it again. She has compiled a comprehensive surface-by-surface ranking, and indulged in a few interesting exercises that remind me of Game Theory. Enjoy, everyone, and thanks again for doing such a thorough job, Rosia! - PB]]

Hot on the heels of our head-to-head exercise, I’ve done some additional digging on another interesting aspect of a player’s overall quality and consistency – comparative performance and versatility by surface.

To start, I took the points earned by the top 60 players in the "Best-of-Eighteen" system (I did not include points earned on the Challenger circuit, largely the domain of newcomers or comebackers, like Guillermo Canas) In addition to excluding Canas's Challenger points, I also docked Dmitri Tursunov, Dominik Hrbaty, Mardy Fish, Olivier Rochus, Julien Bennetteau, Florian Mayer, Hyung-Taik Lee, Marc Gicquel, Benjamin Becker, and Gael Monfils (The latter played a Challenger in March, presumably anticipating a sharp loss of points from his quick start and excellent results on clay  last year).

My first table shows each player’s points broken down by surface: hard, grass, and clay. I folded the synthetic and carpet points in with hard courts, partly because those surfaces are most like hard courts. Given the significant variation in the speed and playing qualities of various synthetic surfaces, they're best lumped in with hard. I had to draw the line somewhere.

As each player is ranked relative to the other 59 men considered in the sample, these shouldn't be considered entirely "true" rankings. Some players off my radar (that is, ranked below No. 60 in the ATP entry rankings) have more points on a given surface than some players within the Top 60. But apart from the minor quirks that might embody, I think this is a fairly reliable surface ranking. About one thing there is no doubt: only two players, Roger Federer and Rafael Nadal, rank in the Top 10 on all surfaces.

Now, for some noteworthy facts:

Roddick, the overall World No. 3 (and No. 2 on hard courts) ranks just 46th in this sample on clay. And Nikolay Davydenko, No.  4 in the entry ranking, has only 5 ATP points on grass, for 47th place. No. 5 Tommy Robredo isn't much better off. He's just 40th on grass, but an impressive No. 3 on clay. The ranking of other players also goes over a cliff on certain surfaces: Novak Djokovic is a respectable No. 8 on clay and hard, but merely No. 18 on grass.

The hard court rankings are most likely to reflect "real" prowess on that surface, simply because they represent 59.3% of all the ATP points I've culled - that's fully  twice as many points than are on offer on clay,  which accounts for 29.8% in my sample. The grass rankings are the least meaningful, as they are generated from only six tournaments (but one of them is this little event played outside London,called Wimbledon). Grass events accounted for just  10.9% of the points. So, really, there may not be such an animal as a “grass court specialist” – just players whose games are well-suited to grass.

I thought I’d play a little further with the rankings. Calculating a player’s average ranking across the three surfaces gives us a crude idea of a player’s overall versatility – the better the average ranking, the stronger the all-surface performance. Significant lack of performance on one surface will pull that average down. Predictably, Federer has the highest average ranking at 1.3, and Nadal, the world number 6 on hard courts, has an average ranking of 3. Our next best performers on this basis, in order, are Novak Djokovic, Tomas Berdych, Mario Ancic, David Ferrer and Ivan Ljubicic. Lack of points on clay or grass pulls down the average ranking of several top 10 players. However, it leaps out that no-one in the current Top 10 without being highly ranked on hard courts.

I tried another fun exercise: I weighted the points so that each of the three surface categories accounted for 33.3% of the rankings. This, in effect, reduces the influence of hard courts, leaves clay slightly more important, andgreatly  inflates the value of grass. Federer and Nadal still rule, but now we have a surprise No. 3:  Mario Ancic, and an impressive No. 4 in Djokovic. Assigning equal weight to all surfaces despite the great difference in the number of points available on each also helps Roddick, who winds up No. 5. This "fantasy ranking"  shows how things might work out if roughly the same number of events were held each year on each of the three major surfaces (remember, there isn't a single Masters Series event on grass).

I also ran a Fantasy Ranking based a a role reversal between clay and hard - that is, if clay enjoyed the proportional advantage that hard courts have in the real world. In that scenario, Federer would still be number one on 6,355 points, but Nadal would only be 114 points behind him. Robredo, Davydenko and Djokovic would be the next three, in that order, but they each would have fewer than half the points of the number two. Roddick and Blake would respectively be ranked 12 and 18 - perhaps earning each of them the designation, “hardcourt specialist."

Finally, because there are so many different types of hard courts, I broke down these points further. Outdoor hard courts account for 67 % of Top 60 hard court points, with 18% on indoor hard courts and 14% on indoor carpet. This yields - at long last! - a category in which Federer is overtaken by someone other than Nadal. In fact, two players: Ivan Ljubicic and and Fernando Gonzalez are marginally better performers on indoor hard courts. Federer not only dominates outdoor hard courts (largely because of his Slam points), but he is also the Indoor Carpet King, thanks to his wins in Shanghai at the Masters Cup and at his home tournament in Basel.

Meanwhile, one of the secrets of Kolya the Obscure’s success can now be  revealed – close to half of his hard court points were won on fast indoor carpet, the surface on which he is number 2 in the world, at the Paris Masters and in Moscow.

--- Rosangel