Tennis stars Pete Sampras and Venus Williams entered this year's U.S. Open as the favorites. Both were coming off impressive victories seven weeks earlier at Wimbledon. But the reigning kings and queens of the hardcourt share another similarity: acupuncture.

Of the two, Sampras has enjoyed the greatest success with the ancient Chinese procedure. In the early rounds of Wimbledon, his chances of winning for a record seventh time appeared nil. He seemed disheartened, and acute tendinitis in his left shin curtailed his mobility on the court. But halfway through Wimbledon, Sampras came alive, advancing to the final, where he defeated Aussie Patrick Rafter.

In the men's dressing room, there was grumbling about Sampras faking it. The shin injury wasn't as serious as he had let on. Even though most had heard about him visiting a London acupuncturist for the shin, few put much faith in such treatment.

In winning Wimbledon, Sampras exhibited newfound energy--often a benefit of those going under the needle.

Heading into the U.S. Open in New York, Sampras had stopped trying to explain his sudden turnabout.

"I'm tired of talking about the injury," he says. "A lot of players think whatever they think. You can just tell. But I've always prided myself on getting through."

Left unsaid was that the top star in men's tennis may have discovered a new way of "getting through" with acupuncture. In winning Wimbledon, Sampras exhibited newfound energy--often a benefit of those going under the needle.

Acupuncture practitioners employ needles with rounded tips that slip a quarter of an inch into the skin. A therapist then gently twists or twirls them, or simply leaves the needles in for up to 10 minutes. Some acupuncturists also stimulate the body's healing powers with a weak electrical current or with heat, burning herbs such as mugwort.

A University of Maryland study estimates that 1 million Americans use acupuncture to treat aches and pains. The U.S. National Institutes of Health states that the treatment is helpful for headaches, low back pain, carpal tunnel syndrome, asthma--even tennis elbow.

But Sampras and Williams have tried acupuncture in different areas with various degrees of success. While Sampras has refused to further discuss his treatments for his shin, Williams tried everything, from massage therapy to acupuncture when she developed tendinitis in both wrists last fall. She eventually took six months off, and some feared she might have to retire from the sport. In her case, acupuncture didn't appear to have an immediate effect; Williams isn't quite sure why her tendinitis lifted. But she did join Sampras in the winner's circle at Wimbledon's Centre Court.

Robert Duggan of the Traditional Acupuncture Institute in Columbia, Maryland, cautions that acupuncture and those who practice it don't set out to "fix" a specific ailment or disease.

"[An] acupuncture student is reminded repeatedly not to label a patient (nor allow patients to label themselves) with disease words: asthma, arthritis, fibromyalgia, chronic fatigue, or even the expressions that often appear in Oriental medicine, such as 'Rising Liver Fire' or 'Water Causative Factor' or 'stuck chi,'" Duggan wrote in Meridians magazine.

Instead, he urges those involved in acupuncture to remember that the needle is just one part of healing. What practitioners do while using their tools, Duggan says, is to remind their patients of "living fully."

As one who has practiced acupuncture for 25 years, Duggan says he knows "very well how essential the needle and other therapies can be in moving forward the healing process." Still, he fears "that emphasizing the power of these techniques will obscure the fact that they are only one element of a much more complicated process--the awakening of an individual's own healing process."

Perhaps without fully realizing it, that's what Sampras and Williams have done.