Players and fans worldwide know that clay-court tennis differs in various
ways from the game on hard courts. On clay the ball is slowed considerably in
bouncing, while on paved surfaces the bounce is usually faster and higher. Moving
to net is thus riskier on clay, as the opponent in back court has extra time
to reach the ball and prepare for the reply. Meanwhile strong serving is
comparatively less helpful on clay, as the surface neutralizes the serve's velocity
and the effect of slice (sidespin). Defensive play is helped on clay,
attacking play on hard. Shoe traction is poor on clay, favoring the player
experienced in moving on it. These differences become exaggerated at high levels of the
game, especially in men's tennis, and as a result two populations of male pros
seem clearly recognizable--players whose strengths are best suited for (1)
clay-court play and (2) hard courts, respectively.
Members of the second group--the hard-court players--tend to rely on very
powerful serves and attacking styles of play. They are more willing to take the
ball early, on the rise, and more willing to move to forecourt. Typically the
forehand is the primary ground weapon, and hard-courters often employ the
one-handed, sliced backhand. In contrast, the clay-courters are more patient in
their forehand attacking and are better able to deliver strong ground strokes with
good consistency--i.e., avoiding errors. Their ground strokes, forehand and
backhand, are regularly delivered with heavy topspin as well as pace. (Too soft
an offering invites domination by opponent.) Clay-courters tend to have very
good court mobility, enhancing defensive play. Clay players are comfortable
sliding their feet into ground strokes, minimizing effort in stopping. They are
content when operating far behind the baseline, where their heavy artillery
can sometimes produce big effects. Some are highly skilled in using the drop
shot, where the clay bounce helps keep the ball low and short, and in winning the
ensuing cat-and-mouse exchanges. The clay-courter's net game may be solid,
but he prefers to win points patiently, often from deep.
Our sketch, above, is certainly overdrawn. But we can explore numerically our
general observation--that there are two distinct populations of players--by
comparing results of the higher pros on the two surfaces. We use tournament
results of the 21st century (years 2001-2004) to calculate each player's strength
on clay and on hard courts, respectively. Our clay data are taken from the
French Open and the three Master's Series clay events (Monte Carlo, Italian, and
German Opens). Hard-court results are from the Australian and U.S. Opens and
two leading outdoor hard-court events (Indian Wells and Key Biscayne). We give
extra weight to the Slams (ratio 5:3) and to more-recent results.*
Our results agree fairly well with intuition. Listed just below are those
members of the current ATP top 100 (entry system) whose clay-court success has
most surpassed their hard-court success. Note that we are not showing the best
or most-successful clay players but rather the ones whose strengths are most
slanted toward the clay-court (and comparatively less slanted to the hard-court)
- Verkerk (Netherlands)
- Ferrero (Spain)
- Robredo (Spain)
- Mantilla (Spain)
- Kuerten (Brazil)
- Saretta (Brazil)
I was surprised that the player atop our list--the player most favored on clay
over hard-- turned out to be a 6-3, 200-pounder from The Netherlands, a
player best known for his extremely powerful serve. But Martin Verkerk, now 25,
considers his backhand also a prime strength, and deems that his best surface is
"clay and slow hard courts" (quoted from ATP material). Our data on Verkerk
are somewhat thin, coming mostly from tournaments in 2003. But the message is
strong. In the big clay events of 2003, Verkerk accumulated a W-L record of 9-3,
including a final-round appearance at Garros. Meanwhile his W-L record in our
sample of hard-court events of 2003 and early 2004 was 2-5. (If we add in
the other two Masters Series outdoor hard events of 2003, Canada and Cincinnati,
his hard-court record becomes 3-7.) His propensity for clay is thus evident.
His performance in lesser events shows the same tendency.
Our runner-up, with score not far behind Verkerk's, was last year's Garros
champion, Juan Carlos Ferrero. His high position as a clay specialist is also
surprising, as the Spanish 24-year-old is a fine contender on hard courts as
well. But his hard-court championships have been rare, while The Mosquito has
achieved a steady stream of triumphs on clay. His excellent court speed and
relatively thin physique seem well adapted to the clay game.
We note that five of our six purest clay performers are from Spain or South
America--regions where most youths learn the game on clay. Five of our second
six** are also from these places. World #4 Guillermo Coria almost dropped out
of our second group by recent strong results on hard courts at Indian Wells,
which reduced the extremity of his score calculated here.
What about the other extreme? Who are the members of the ATP top 100 whose
successes on outdoor hard courts have most surpassed their performances on clay?
Our answer again begins with a mild surprise--a former champion and twice
runner-up on clay at Roland Garros, but nevertheless a player who now plainly
registers as a hard-court performer.
- Agassi (U.S.)
- Hewitt (Australia)
- Roddick (U.S.)
- T. Martin (U.S.)
- Blake (U.S.)
- Srichaphan (Thailand)
Watchers of Andre Agassi in the last few years know that Andre's court
tactics are now in the pattern of the archetype hard-courter, described earlier.
Though he remains a strong clay player, his remarkable success in his favorite
realm in recent years produces a substantial margin over his clay results.
Lleyton Hewitt, too, is perhaps a surprise as runner-up here, as Lleyton's
speed--comparable to Ferrero's or Coria's--would seem to point to clay-court
strengths. Probably it is that Hewitt's relative inexperience on clay fails to equip
him against the top clay players on their favored surface.
Four members of our six are from the United States, clearly mirroring the
high proportion of hard courts in that country. Our second six*** are more
diverse geographically, including Escude of France, Safin of Russia, and Nalbandian
of Argentina. Note that Pete Sampras and Pat Rafter, who are not listed here
because they are no longer in the ATP top 100, accumulated results in 2001 and
2002 that would place them near the top of our hard-court-advantaged list
here. Note also that Roger Federer, the current World #1, scores very high on both
surfaces. But in comparing his clay and hard-court scores, he clearly rates
on the hard-court-preferred side of the curve though not to extreme.
An interesting confrontation between archetype performers of the opposite
groups took place at Indian Wells last month, telecast by ESPN. Hard-courter
Andre Agassi and clay-courter Guillermo Coria had met four times previously. Andre
won their three meetings on hard courts including last year's Australian and
U.S. Opens. Guillermo won their only encounter on clay, at French Open 2003.
Now at Indian Wells, Agassi played his patented style, hammering away with
crisp, flattish drives to the sides from hitting positions close on the baseline.
Coria showed his superb court mobility, along with firm and consistent topspin
drives from both sides. Agassi's greater physical strength translated into
stronger serving, especially in his second serve, and greater groundstroke
penetration, which generally forced Coria to the defensive. Typically Agassi
returned serve from on or slightly inside baseline, Coria from well behind.
Wonderful shotmaking by Coria kept matters close, but Andre finally prevailed 6-4 7-5,
thus continuing his success on hard courts over the Argentine star. It was a
picture demonstration of the differences between the modern clay-court and
The results of our calculations largely conformed to expectation in pointing
out those players who most prefer clay and those who most prefer outdoor hard.
But how justifiable is it to deem the two populations to be distinct, where
most players fall into one or the other group? Or is it more accurate to
envision a continuum of strengths and styles, where most players fall into a middle
range along a spectrum of difference?
We can obtain a qualified answer by plotting a bar graph showing how the
scores of our player population are distributed. Please see the below plot of
data showing distribution of scores for the ATP top 50. Clay-court scorers are
toward the right, hard-courters to the left. We detect two distinct humps
either side of neutral, divided by a seeming valley. Thus the graph appears to
support our notion of two somewhat exclusive populations--one skilled on clay,
the other in hard-court tennis. (The valley is not seen in graphing the ATP
second 50, probably because scores of these players on the separate surfaces are
not large and thus the differentials tend to be smaller--i.e., clustered more
closely around zero.)
OUTLOOK IN WOMEN'S TENNIS
Injuries continue to sideline many of the top women. Wrist trouble forced the
withdrawal of Kim Clijsters just prior to Pacific Life Open at Indian Wells.
Justine Henin-Hardenne and Lindsay Davenport remained the only contending
superstars in that event, both of whom reached the final round without losing a
set, Henin then winning. The luster of women's tennis seemed to depend on the
return of the wounded warriors, especially the Williams sisters. The sisters
played in the Nasdaq-100 at Key Biscayne this week, but both Henin and Davenport
skipped the event.
The recent dominance of Henin-Hardenne over the others may prove short-lived,
but it is assuredly pronounced. Though her physique seems slender, Justine
generates amazing power, blending pace and spin with remarkable control. Her
picture backhand remains superb, but it is now her second-best groundstroke, as
her forehand is absolutely punishing from anywhere on court.
The remarkable progress of the young Russian women remained evident at Indian
Wells, where teenager Kuznetsova--the only player to have won a match from
Henin this year--again played well. The Russians made a good run in overcoming an
early American lead in total matches won. But matters turned to favor the
Americans in the semi-finals of the singles, where Davenport advanced over Dechy
and Myskina lost to Henin. Meanwhile Kuznetsova-Likhovsteva failed to pick up
a win in the doubles final. The Russian women thus finished one victory behind
The Russians took the early lead at Key Biscayne, placing seven women into
the third round of singles against the U.S.'s six. With Myskina scratched and
with the Williams sisters still in the singles and Navratilova-Raymond in the
doubles, the Americans at that point seemed likely to repeat their margin at
The month of April will bring the women's early clay events in Europe and the
United States. First round of Fed Cup takes place in the month's third week,
though none of the favorites--last year's semi-finalists Belgium, France,
Russia, and U.S.--will meet head-to-head. The Williams sisters have been named to
the American squad.
MEN'S TENNIS OUTLOOK
Early April brings the second round of Davis Cup. Just a month ago, the
Swedish squad seemed strong and deep enough to be likely winners over the Americans
in their forthcoming meeting at Del Ray Beach. But Joachim Johansson faltered
in the qualifiers at Indian Wells, and none of the Swedish stars reached the
final sixteen of that event. But four Americans (besides Agassi) did so, and
Roddick and Blake reached the last eight. Then at Key Biscayne American Vince
Spadea upset Safin in early play. Thus Captain McEnroe's choice of the four-man
playing squad became unusually difficult. He picked Mardy Fish to join
Roddick and the Bryans. The Swedish foursome is Bjorkman, Enqvist, Soderling, and
Meanwhile Roger Federer seems likely to win two singles matches in
Switzerland's meet with France, but the French should win the other two singles and the
doubles. (Swiss doubles pair Allegro-Federer won only one match at Indian
Wells, while Clement-Grosjean of France upset the Bryans and went on to win the
tournament.) In the other two coming Cup meetings, Spain and Argentina should be
safe on home-country clay against European opponents, though Netherlander
Verkerk's 2003 successes on clay suggest trouble for the Spanish hosts.
The clay season in Europe and the U.S. will commence immediately after Cup
weekend. The month will include the year's first clay-court Masters Series
event, Monte Carlo Open, won last year by The Mosquito. We offer the following
rank-order of favorites for the clay season. Our list comes from the data used in
the analysis discussed earlier. These are the players of the ATP top 100 who
show the best clay success independent of results on any other surface.
Our highest-ranked artist, Ferrero, has been sidelined recently with chicken
pox, so that second-ranking Federer seems likely to claim some new clay-court
triumphs. Gustavo Kuerten's third-place score here stems mainly from the early
years of our study. Fourth-ranked Coria announced his current readiness by a
strong recent showing at Indian Wells and in early play at Key Biscayne. There
remain hosts of others capable of defeating a front-runner who is at less
than his best.
Last year the European clay events prior to Garros were not seen on U.S.
television except in places where Tennis Channel was available. It appears that
the same condition will prevail in 2004.
* Using the twelve clay-court tournaments held during 2001-2003 and named
above, we take each player's best six results and calculate from them a weighted
average score. Similarly, from the 14 hard-court events (through Indian Wells
2004), we obtain a weighted average of each player's best seven. Performance
in a given tournament is measured by how far the player advances, adjusted for
(1) sets won and lost, (2) tiebreak sets lost and won, and (3) strength of
last opponent as shown by the opponent's success in later rounds.
** Here is our second six of extreme clay-courters
7. Ancic (Croatia)
8. Zabaleta (Argentina)
9. Blanco (Spain)
10. Horna (Peru)
11. Coria (Argentina)
12. Portas (Spain)
*** Here is our second six of hard-courters.
7. Escude (France)
8. Bjorkman (Sweden)
9. El Aynaoui (Morocco)
10. Dent (U.S.)
11. Nalbandian (Argentina)
12. Safin (Russia)