BEIJING -- When playing at the 2-meter line in water polo, what happens beneath the surface stays beneath the surface.
If you're driving your knuckles into the other guy's ribs, do it with a straight face. Kneeing him in the kidney? Try to keep your hands busy so no one suspects. Even if the scrum gets worse than that, betray no emotion.
And it can get worse than that.
"I've had my eyes gouged, [testicles] grabbed, gotten stitches," American center Ryan Bailey said. "There's tons of stuff that happens."
You even hear about some centers who have been the recipients of uninvited prostate checkups. (Think Chevy Chase singing "Mooooon Riverrrrr" in "Fletch.")
That's Olympic water polo -- a fierce sport above the water line and an international street fight below it. The key is to pretend none of it bothers you -- because once you start retaliating or losing your cool, that's when the refs take notice. A good center comes with the face of a poker player and the hands of a felon.
For the first time in years, the Americans are an Olympic water polo force, advancing to the semifinals in men's play and winning the silver medal in women's play. To get this far, they've had to play with skill, teamwork and confidence. A little underwater brutality hasn't hurt, either. It's part of the sport -- just don't get caught.
The officials can't call what they can't see, and what they can't see is enough to make a Marine cringe.
Water polo is a great sport with an odd corporeal obsession. Maybe it's all the time spent in those small suits. You attend a U.S. practice, and coach Terry Schroeder is bare-chested indoors. Assistant coach Robert Lynn is wearing neither shirt nor pants -- he's walking the deck with whistle and clipboard in a Speedo bikini.
Once the ball is in play, these Olympians are as physical as boxers, wrestlers and martial artists. Except they're doing it while treading water. Try mugging someone while working furiously to keep your head above the surface.
When it gets bad is when people try to take the eyes out. That wakes you up, when someone does that to one of your teammates. Then, when you get your chance, you take your shot and send that guy to the hospital, too.
--U.S. assistant coach Robert Lynn
The roughest stuff happens at the positions of center and center defender, the two players who maul each other at the 2-meter line in front of the goal. Think of the most physical post play allowed in basketball, then multiply it to the verge of assault and battery.
"You have to be a sponge for punishment," Lynn said.
Many want to play center. Not a lot of them last, Schroeder said. They weed themselves out based largely on their ability to dish out and endure punishment.
"You really need to be able to take a beating," said Schroeder, a center himself during his playing days. "You're getting hit over the head with a 2-by-4, and you still have to stay focused on the task at hand, which is directing the offense.
"It's pretty brutal in there, and there's a lot the referees don't see."
That is the hidden art of playing center or center defender. You have to be able to get away with well, not outright murder, but at least a little mayhem.
Bailey, who has played professionally for years in Europe, is articulate and engaging. He's also 6-foot-6 and a sculpted 245 pounds, and would not look at all out of place in an NFL locker room. His 5 o'clock shadow is in full effect by noon.
In other words, he's perfect for the job of playing center -- with one flaw. When play gets dirty, his face gets red and gives him away.
"I'm a big guy, and I like to be physical in there," he said. "It's a one-on-one battle. It's really not fun a lot of the time, but it's my job. I just try to keep a straight face and hope it doesn't turn red."
You have to be a con man, using every trick -- and body part -- at your disposal. If you've taken a cheap shot, you might try to subtly deliver an elbow to the nose while swimming to the other end. If you get a chance to grab an opponent's hand, try to break a finger -- especially a thumb. That reduces his ability to catch, pass or shoot the ball.
Lynn recalled a Hungarian player who used to stick his foot in the suits of opposing centers -- Schroeder among them. Lynn said Schroeder even tried taping his suit to his body to keep the Hun's foot out, to no avail.
Eventually, Lynn said, a Croatian applied a shot to the guy's jewels and put him in his place.
As a center defender, Lynn sometimes approached his work like a hockey goon -- even referencing Marty McSorley, Wayne Gretzky's longtime enforcer sidekick. Lynn was there to play water polo until someone took a cheap shot at him or one of his teammates.
"As long as it's clean, I'm playing clean," he said. "If someone starts trying some stuff, watch out. It's on.
"First time, let me move your ear guard. Next time, I'm breaking your ear. Maybe knuckles in the eye, see if they panic. When it gets bad is when people try to take the eyes out. That wakes you up, when someone does that to one of your teammates. Then, when you get your chance, you take your shot and send that guy to the hospital, too."
Speaking of the hospital: American backup center J.W. Krumpholz found out what international water polo is all about at age 13.
That's when the Californian found himself in a Serbian emergency room, where a doctor with a cigarette dangling from her lips examined his gruesomely gashed left eye. He took stitches to the inside and outside of his eyelid, and nearly had a detached retina.
That was seven years ago. Today, Krumpholz can endure and inflict punishment like a seasoned veteran.
"That's why we play center," he said. "It's awesome."
It's all fun and games at water polo until someone loses an eye. Or gets a foot in the suit.
Pat Forde is a senior writer for ESPN.com. He can be reached at ESPN4D@aol.com.