Seeding: Key to Competitive Tourneys

The system ensures that top tennis players do not meet in the early rounds

Seeding is the system in professional tennis used to separate the top players in a draw so that they will not meet in the early rounds of a tournament. The top seed is the player the tournament committee deems the strongest player in the field. He and the second seed are placed at opposite ends of the draw so that, if they both keep winning, they will meet in the final round. The number of seeds is based on the size of the draw.

The Wimbledon Example

Wimbledon, held annually in London and the world's oldest tennis tournament, provides a perfect setting to discuss how seeding works. Though Wimbledon doesn't use a committee to determine how players are seeded, it does use a specific, numbers-based metric to decide player seedings for the venerable tournament.

Following how Marin Cilic, the 2017 tournament's runner up, and Roger Federer, the eventual winner, made their way to the men's singles final, illustrates how seeding works in tennis. The key to seeding is that officials in any tournament don't want the top players to play against each other early, which would only serve to eliminate many top players long before the finals — and allow lower-ranking (and less capable) tennis players to survive deep into the tournament. 

In the end, without proper seedings, tennis superstars would be left on the sidelines, while quarterfinal, semifinal, and final matches would be lopsided contests.

Though Cilic and Federer were not the top-seeded players at Wimbledon 2017, they were close. And, as a result, the matches they played were highly contested and engaging.

Determining Rankings

For Wimbledon, seeding has been based on computer rankings since 1975, according to the tournament website. The seeds are the top 32 players on the Association of Tennis Professionals (ATP) rankings, but they are then "rearranged on a surface-based system," Wimbledon says.

"It is based on giving additional credit for grass court performance in the two year period immediately before the date used for seeding for The Championships."

For the 2017 tournament, Wimbledon determined seeding by:

  • Taking the player's ATP Ranking points as of June 26, 2017
  • Adding 100 percent of the points earned for all grass court tournaments in the immediate past 12 months period prior to June 26, 2017
  • Adding 75 percent of the points earned for the best grass court tournament in the 12 months prior to that

The reason that Wimbledon places such a great emphasis on how players have performed on grass courts is that the tournament is played on grass. (Some tournaments, by contrast, are played on clay courts.)

Federer vs. Cilic

By Wimbledon's standards, Federer's rating metric was as follows, according to the website Tennis Warehouse, which tracks metrics for tournaments:

ATP ranking points4945
2016 grass points900
75 percent of 2015 best grass points900
Total seeding points6745

This earned Federer the third seed in the tournament. Andy Murray, by contrast, was seeded No. 1, with about 1,000 more points than Federer. Cilic, who earned about 1,000 fewer points than Federer, was seeded No.7.

The Results

As a result of the rankings, Federer and Cilic never met in the early rounds — and, indeed, only met when they both made their way to the finals.

Both played unranked players in the early rounds. In Wimbledon, and at other tennis tourneys, unranked players can earn their way into top tournaments through play-in tournements. For Wimbledon, these are small, less-publicized tournaments held in Britain and other locations.

So, Cilic played Philipp Kohlschreiber, an unranked player from Germany, in the first round and beat him in straight sets. In the first round, Federer played unranked Alexander Dolgopolov, who withdrew midmatch with an injury. In the second round, Federer played unranked Dusan Lajovic of Serbia and beat him in straight sets. In the same round, Cilic played Florian Mayer and beat him in straight sets. And so on.

Because of the way they were seeded, Federer did not play a ranked player (No. 27) until the third round, while Cilic did not match up against a ranked opponent (No.26) until the same round.

As they progressed through the tournament, Federer and Cilic finally began to play against high-ranked players in the quarterfinals, the semifinals and, of course, the final, where Federer beat Cilic 6-3, 6-1, 6-4.