In this excerpt from The Courts of Babylon, ace tennis writer Peter Bodo describes how tournament fields are selected from entry rankings, wild cards, and qualifiers.

p. 68-69

This is how the tournament system works in the pro era: Grand Slam tournaments and ATP Tour or WTA Tour events accept players on the basis of their world rankings, which are generated by sophisticated computer programs. The higher a player's ranking, the better his chance of being accepted into the field, or "draw." The only exceptions to that rule are qualifiers and wild cards (more about them later) who can take places held open after the main draw has been filled by the highest-ranked players seeking entry.

A two-week Grand Slam event has a draw of 128, while a typical one-week tour event has a draw of 32. Of those 128 places in a Grand Slam draw, 16 are reserved for qualifiers and 8 for wild cards [these numbers have now been adjusted slightly to enter more wild cards, or players in exceptional circumstances, so there are slightly fewer "automatic" rank based openings], leaving 104 places that are filled solely in order of world rankings-- rankings that are generated by a complex formula worked out to rate a player's performance over the previous twelve months. Events with smaller draws have proportionately fewer places for qualifiers and wild cards.

Thus, the number seventy-five player in the world is assured of a place in the draw of Wimbledon, but whether or not he is "straight in" in a popular one-week ATP Tour event with a draw of thirty-two is questionable. It all depends on the cutoff number, which is a function of how many players want to play the event and how high their rankings are. During a week when there are two or three tournaments in progress in different parts of the world, the number seventy-five player has a good chance of getting into an event with a draw of thirty-two, even though he is not one of the top thirty-two players in the world. It all depends on how many of the players ranked above him are playing elsewhere or not at all.

So the maximum number of players in any tournament is 128, yet the ATP and WTA tours rank 500 players each [over a thousand each now], and behind them are thousands of other players who would love to get a shot at playing the pro tour. That's where qualifiers, wild cards, and the plethora of "satellite" circuits and Challenger tournaments come into it. Theoretically, anybody can have a wild card into Wimbledon or the U.S. Open, and that includes you and me. Wild cards are rendered at the discretion of the promoter or tournament director, but they are usually given to promising junior players, aging champions who remain gate attractions despite being in semi or full retirement, and quality players who have lost their rankings because of unusual circumstances such as a long layoff because of injury. The competition for wild cards is fierce. Promoters use them to enhance the marquee value of their events. Player agents wheel and deal with promoters to get them for promising juniors, and each of those parties uses the wild cards as a tool for building credibility with the prodigy and his or her parents.

Qualifying is the real door to the big time for players who do not automatically earn entry into tournaments because their rankings are not high enough. The sixteen places reserved for qualifiers at Grand Slam events go to players who earn the berths in the qualifying event that immediately precedes the tournament. With five hundred players holding official rankings, the qualifying competitions can be fierce, but they enable a player to leapfrog over those ranked above him, right into the big time, if he or she has the game to do so.

from The Courts of Babylon: Tales of Greed and Glory in a Harsh New World of Professional Tennis Scribner; ISBN: 0684812967; June 1995, out of print usually available used from ABE Books or Amazon.com

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