NEW YORK -- On tennis courts across the world, young women players aren't just toting rackets endorsed by their favorite stars -- they're imitating the racket the players make on the court.
"Today's grunters are all the top players," said Boston Globe columnist Bud Collins, "so they're going to be emulated."
Grunting is more prevalent than ever before and with Maria Sharapova, Serena and Venus Williams among the top vocalists, it's trickling down to those first taking up the sport.
"It started with Monica Seles because she sort of set the bar with grunting," said Lawrence Kleger, executive director of tennis for Sportime Clubs in New York, where many kids come to hone their skills. "You hear the grunting a lot more around here and the top-level juniors are doing it all the time."
Serena admits to becoming a grunter partly out of idol worship.
"When I was younger I used to love Monica Seles," Williams said. "She was like my role model. I loved her game. I loved her grunt. So my grunt is kind of like hers a little bit, where it's like a double-grunt. Instead of just like one long one, it's like two of them."
Williams, like many players, sees grunting as a way of breathing. While top tennis coaches typically teach athletes that breathing is an important part of being an efficient athlete, they rarely encourage grunting.
"I did have one coach tell me I should grunt on every shot so at least when you lose, it looks like you are trying," said Vince Spadea, who holds the ATP Tour record for the most consecutive losses (21). "It had some merit to it."
Still, Spadea -- an occasional on-court grunter -- isn't quite sure about how it made its way into a sport where the audience is asked to be quiet for the majority of the contest.
"Usually grunts come from a different situation, like a fistfight or an intimate type environment," Spadea said. "That's when you know you are giving it all."
It's not clear who grunted first. Collins says his first grunting memory is of American junior Vicki Palmer in the 1960s. Since then, women -- more often than men -- have made it their habit.
"Seles was minor league compared to the women that are playing now," Collins said. "It's definitely louder and more imaginative."
Grunting has been the source of much debate in recent years. It seems to always come to a head during Wimbledon, where British papers have measured the sound eminating from some of the WTA's top stars.
Sharapova's cry reportedly measured 100 decibels, allegedly the same level as the sound of a small airplane landing. Serena placed second, at 88 decibels, while her sister Venus registered 85 decibels.
Two years ago, when American youngster Ashley Harkleroad faced Sharapova at Wimbledon, Harkleroad screamed across the net, "louder." The crowd laughed.
"I try not to make noise, but it's just something I've been doing all my life since I've been playing tennis," Sharapova said after her victory. "It's something that I try to control but my mouth doesn't control the way I play. It's just a mouth."
This year, Wimbledon referee Alan Mills told Reuters that he wanted the shrieking to stop. Nothing was done. Sharapova and Williams then proceeded to squeal their way through a semifinal match that might forever be known as the loudest in women's tennis history.
"I never heard anything like it," said Tracy Austin on USA Network's broadcast of Sharapova's Monday night match where the 18-year-old Russian was very quiet in her 6-1, 6-1 victory over Eleni Daniilidou. "Anything is going to be more quiet than that."
Sharapova -- who has been dubbed the "Bawl-Breaker," by the London Sun and "The Siberian Siren" by Collins -- doesn't like to talk about her grunting habit.
"I don't pay attention to it," she said after Monday night's match.
But if Sharapova sounded quieter on Monday night, it might be because she has quietly been working on it.
Robert Landsdorp, who has been coaching Sharapova since she was 10 years old, said that about a month ago, he worked specifically with Sharapova to lessening the volume of her grunts.
In the beginning, Landsdorp said, it bothered her to stop shrieking and she couldn't hit the ball as well. Today, he says she's not making as much noise as she used to make.
"It's just so irritating to the people watching," he said. "It sounds like there are peacocks out on the court."
There are some that think grunting is used as a tactic to throw off an opponent.
"It could be so annoying that it gives a person an edge," Kleger said. "Some think that anything you can do to annoy your opponent is fair game."
Richard Williams doesn't think his daughters use their grunts in order to intimidate their competition. He says it's a necessary noise that has just become part of the game.
"It more or less has to do with timing," said Williams, noting that he didn't teach Venus and Serena to grunt. "I don't think anyone should do much complaining about it."
In 1992, Seles listened to all of those criticizing her grunt and played a grunt-less Wimbledon final against Steffi Graf. After Seles was thumped, winning only three games, many speculated it was because she was concentrating too hard on being quiet.
"I didn't lose to Steffi today because I was not grunting," Seles defiantly said after the match.
If players embrace their unique grunt, it's possible they could one day make money off it, according to Robert Kunstadt, a New York-based patent attorney. Kunstadt says that some sounds -- like MGM's lion roar -- are patentable and could one day be enforced.
He can't make the exact sound of the MGM lion, but an actor in a recent Lexus commercial suggests to Andy Roddick that his grunt "should be majestic, like a lion."
When Roddick can't match the woman's impression (Rug-A-Gug-Ah-Rah), she tells Roddick that he's not a good grunter.
The men don't get as much attention for their grunting -- perhaps because it's less obvious and doesn't necessarily involve as many of the top players. Sampras never made noise, neither does Federer. Notable grunters on the men's side include the clay-court specialists -- Rafael Nadal, Guillermo Canas and Albert Costa.
As long as it garners attention, some sports marketers say that the women should be proud of their vocal expression on the court.
"It only adds to the symbolism of their sexuality that they are often trying to sell," said Bob Dorfman, sports analyst for Pickett Advertising in San Francisco. "Then they can grunt over a Coke or a piece of exercise equipment."
Darren Rovell, who covers sports business for ESPN.com, can be reached at firstname.lastname@example.org.