Tennis players know it's important to get their first serve in, but for some it's more important than others.
There's usually a significant difference in how often players win the point when they get in their stronger first serves as opposed to a more cautious second serve. Statistics kept by the ATP show that for this year, Milos Raonic led the tour in the percentage of first serve points won at 82 percent, and Novak Djokovic was on top for second serve points won with 60 percent -- a gap of 22 percent.
Comparing first and second serve points won for individual players is also revealing. Obviously, the percentage of points won does not measure of the effectiveness of a serve alone. Raonic's monster delivery may explain why he wins so many first serve points, but Djokovic's success is not about an outstanding second serve as much as it is about how well the world No. 2 backs up his serve with the rest of his game.
Nevertheless, the difference between a player's percentage of first and second serve points won can indicate which players have games that rely most on their first serves. On the right are the 58 most effective first servers on the men's tour, organized by their differences in service winning percentages.
Sam Querrey is the player with the biggest gap, winning 31 percent more first serve points than second serves. Raonic is next with 29 percent. It's not just the size of the gap that matters, of course. Querrey's numbers are so far apart because he has one of the most effective first serves but is very weak on second serves, while Raonic, though not far behind, is in a much better position with not only the most effective first serve but also a respectable percentage on his second. What isn't different is that both find things much easier when their first serve lands in the box.
Generally, the top consists of a group known for being powerful but erratic, with more than its share of hotheads. But it looks like they have good reason to be frustrated when they don't get their first serves in.
At the other extreme are those for whom hitting a first or second serve makes the least difference in whether they win the point. Many tend to be defensive players who tend not to win a high percentage of points off their first serve. Juan Monaco, for example, gets a relatively poor 65 percent on his first serve but a respectable 53 on his second, a 12 percent gap that is the smallest in the entire group.
But those who have a narrow gap and also manage to win a decent amount of first serve points tend to be better at turning defense to offensive. Naturally, two who stand out here are Djokovic and Rafael Nadal. Their gaps are 15 percent and 16 percent, respectively, thanks to being the two most successful players in second-serve points won as well as in the upper half for first-serve points. Also notable at 19 percent are Stanislas Wawrinka and Philipp Kohlschreiber, known for having a very good serve for his size. David Ferrer, meanwhile, has a gap of only 17 percent but is relatively weak on both first and second serves. Standing at 5-foot-9, serving is not his strength, but his returns are among the very best.
Finding middle ground
The differences between the two ends is even greater in practice because the big-serving players who win a lot of first serve points tend to have lower first serve percentages than the steady types who win more of their second serves. That means the big servers have to hit second serves more often, making those occasions when they do get their first serve in even more important.
Although there are successful players at both extremes, the optimum difference seems to be around 20-22 percent, with the first-serve mark in the mid-seventies and the second-serve mark in the mid-fifties. That's enough for the first serve to serve its purpose of providing a significant edge in a point, but not so much that having to deliver a second serve becomes a big problem.
Players around this mark include John Isner, who is the only player to appear in the top eight of all six serving categories -- including first serve percentage (the number of first serves made, not won). That is particularly impressive because it's a category that tends to be dominated by lesser servers who are just carefully trying to get the ball in. Isner is at 22 percent, along with Kevin Anderson and Feliciano Lopez -- all known for the strength of their deliveries.
When it comes to taking care of first- and second-serve points combined (non-weighted), any approach seems to work as long as it's done well. At the top are Raonic and Djokovic, followed by Isner, Nicolas Almagro, Kohlschreiber, Federer and a three-way tie between Nadal, Tomas Berdych and Anderson.
The collective serving statistics the WTA publishes are limited to the top 10 in each category, but it's no surprise to see Serena Williams' serving dominance reflected in her No. 1 position for first-serve points won and No. 2 in second-serve points won. But even for Williams, there's a significant difference between the two -- 74.7 percent and 51.2 percent respectively, a gap of 23.5 percent.
Among the top women, Maria Sharapova seems to have the biggest gap at 24.2 percent, winning 71.5 percent of first serves and only 46.9 of second serves -- a reflection of those famous serving wobbles. Sabine Lisicki, who has one of the tour's biggest serves after Williams, is also quite far apart at 70.7 percent first serves and 46.9 percent for second serves.
Agnieszka Radwanska, by contrast, has a frail second serve but is one of the most creative defenders on tour. She has a gap of only 14.1 percent, with 65 percent of first serves won and 49.9 percent of second serves. Li Na comes in at 16.3 percent, while Azarenka is at 17.1 percent.
In a game in which margins are small, these differences can be far from minor. So the next time a player steps up to hit a first serve, it'll be clearer just how important it is whether the ball goes in or out.