Goran Ivanisevic, the big-serving 2001 Wimbledon champion from Croatia, once declared that he could produce an ace with virtually any object resembling a tennis ball. "They give me a peach," he said. "I still serve aces with it."
Which is a good place to start a discussion about tennis balls. And how, according to Rick Janes, an expert on the sport's technical aspects, "there are a range of weights and diameters, and no two tennis balls are really identical."
Not only that, but it turns out, to the surprise of many people close to the sport, the U.S. Open is played with two different types of ball -- one for the men's matches, another for the women's and mixed doubles.
This came to light after Andy Roddick's emotion-charged victory over Bernard Tomic the night after Roddick announced last week that this Open would be his final professional tournament. About to serve in that match, Roddick said, "I looked down and . . .
"See, the women use a different ball than we do, and I did what I normally do, get three or four balls and look for the one that looks the lightest to serve. Ours have a black logo, theirs have a red logo. We had a red-logo ball in our mix somehow. I have no idea where it came from."
Roddick thought about serving that ball which, according to doubles specialist Bob Bryan, "is a ball you can hit probably five, six miles an hour faster." Entered in both men's doubles and mixed doubles, Bryan is accustomed to both balls and calls the red-logo ball "a real BB. It flies a lot more, you can shape it a lot more."
But Janes, a technical consultant for the Babolat tennis gear company, past member of the U.S. Tennis Association technical committee and holder of 32 patents on tennis equipment, noted that players "don't live in a scientific world." He isn't sure about Bryan's claim to getting more speed from the women's ball.
"He could be correct," Janes said, "but that's not necessarily the case. A lighter ball slows faster. Think of badminton. When they swing at the shuttlecock, it's going really fast. But, within 6 feet, it literally stops. Like a parachute effect."
According to the USTA, the balls used by the men and women at the Open are "the same in size, pressure and design; the sole difference is that the men compete with an extra duty felt ball while the women compete using a regular duty felt ball."
So, while they described the balls as identical, Janes said that the ball with heavier felt, "if it hits you at 140 miles per hour will hurt more."
Janes noted that court surfaces, clay or grass or hard, dictate the use of slightly different balls, and that the clay-court French Open uses a "harder" ball to facilitate more interesting rallies. He said that ball "goes faster and doesn't spin as much."
Grass-court Wimbledon, in Ivanisevic's time, went to a ball that was two percent softer, and once tested a ball that was larger in diameter, "but players couldn't put any spin on the ball," Janes said, and it was rejected. Along with the peach.