TECHNOLOGY COMES TO GRASS TENNIS COURTS. I have long known that tennis courts differ. For example, grass courts are “faster” than clay courts and favor a quicker player. I did not know that there are measuring devices that are used for tennis courts and for parts of tennis courts. Carl Bialik had an article on the FiveThirtyEight blog about efforts to get more precise and also more portable measuring devices for tennis courts. Court speed ratings are usually in the 20 to 70 range (the faster the court, the higher the number). For Davis Cup matches, a court should have a rating between 24 and 50. Parts of a court may have a different rating (the area near the baseline on a grass court is often faster because of wear and tear from tennis shoes—you can see the difference on television). Individual courts at the same location can have different ratings. Bialik notes that questions about the speed of a court are standard at post-match press conferences at tournaments.
Slight differences are important. A warmer ball will play slower. Bialik says that a ball warmed by being in an opponent’s pocket will play differently—as if the court is slower.