During the 1982 Italian Open, a journalist asked Chris Evert Lloyd what she knew about her next opponent, the up-and-coming 18-year-old Lisa Bonder. "Absolutely nothing," she replied honestly. Who could learn the strengths and weaknesses of every player?
Today Evert Lloyd and 1,000 other players, domestic and foreign, know their opponents' games, and their own, far better because they subscribe to CompuTennis, a computerized analysis service based in Palo Alto, Calif. that provides printouts of as many as 100 pages on a match.
The service was founded by Bill Jacobson, a former South African amateur who had been applying computer technology to projects involving geophysical exploration. Late in 1982 he started charting tennis matches for his son Mark, a ranked junior in northern California. At first he fed hand-collected data into a microcomputer. He soon designed a four-pound portable computer with which a single observer could directly record 10 times as much data.
CompuTennis was on its way when several top junior coaches and the Stanford men's team bought computers on which to produce their own match reports. And last June the service was given a contract by the United States Tennis Association to chart matches for all four national junior teams—Davis Cup, Wightman Cup, Federation Cup and Davis Cup under 18.
Jacobson's computer program doesn't cover every shot in a match. Because players can rally for minutes at a time, the observer records only "key strokes": the serve and return, and the sequence of shots—up to five or six—that lead to the end of the point. The observer can describe the shots (i.e., half volley, passing shot) and note whether they're forehand or backhand, the zones of the court they travel between and the result (i.e., forcing shot, error).
There are console keys on which to record 10 other statistics, such as the number of times a player runs around his backhand. The analyst can also note the surface and weather conditions, and time each point. This fall, with an upgraded program, he will also be able to handle doubles matches.
Since printouts can be produced as a match progresses, television broadcasters can display and discuss constantly updated statistics. Indeed, the system is now available to broadcasters at almost every major tournament, although, perhaps afraid of befuddling viewers, they haven't yet dipped into the most sophisticated aspects of the analyses.
A complete match report provides a blizzard of statistics. Among its choicest categories are ratios of winners to errors for different strokes, tendencies to rely on certain strokes and success rates at the net and from the backcourt.
Working steadily, the CompuTennis staff has amassed a library of data. They've charted 2,100 matches involving more than 1,000 different players. Jacob-son studies this data like a theologian pondering Holy Scripture. He poses questions about tennis and then dives into the numbers for answers:
"Why has Ivan Lendl had more success indoors than out? Because outdoors he gets 20 percent fewer first serves in play than the average pro. He hits a flat, hard serve off a high toss, with very little margin for error, and outdoors the wind can really throw him off.