Budapest(CNN) It's a brutal battle won by the team who can best master its dark arts.
Water polo is not for the faint-hearted and, below the surface, fierce competitors push its rules to the limit.
Away from the eyes of officials, players will kick and punch each other in pursuit of victory.
"We always hold the enemy," Hungarian water polo player Ádám Decker tells CNN. "(We) catch the bathing suit, sometimes punch, (and kick).
"Some (say) the most important things happen under the water."
Hungary head coach Tamás Märcz appears to favor rough play, even practicing moves designed to go undetected by the refs.
"Water polo is like rugby in the water -- or worse -- because the referees cannot see anything," he admits. "Ninety percent of the guys' (bodies) are under the water."
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"We like this kind of playing," he adds. "We practice (how to wrestle) under the water. The guys call this kind of practice 'victory,' (as in) only the victory counts.
"The goal is not to be violent, but sporting aggression is part of our game."
US men's captain Tony Azevedo, however, thinks violence in the sport has gotten out of hand.
"It's definitely the most physical game out there, and the referees don't see what's going on," he told inquirer.net in 2011. "It's a brutal game, and in the end it's not as finessed as you'd like to see.
"You want to see some good goals and nice moves and in the end it turns out to be a boxing match."
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Decker will be testing his combative skills alongside his Hungarian teammates, starting Friday at the FINA World Aquatics Championships.
Once again, the pressure of an entire nation will rest on the teams' shoulders.
Water polo is engraved into Hungary's athletic heritage: The country has won nine of the 26 Olympic water polo events and medaled 15 times, figures that blow its competitors out of the water.
The sport cemented its place as the de facto national pastime following the "Blood in the Water" match in 1956 -- a clash between the Soviet Union and Hungary, that for many reflected the troubles of the two nations during the devastating period of the Cold War.
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The country's historic success has inspired younger generations to try to become the next Tamás Kásás, Hungary's most decorated water polo player who led the team to three straight Olympic golds between 2000 and 2008.
"When we were children, everybody was dreaming about the gold medal," says Märcz, the current coach who was also part of that gold medal trilogy as a player. "Also the same thing (happens) now: All the children who are coming to the pool would like to become Olympic gold medalists,"
Despite Hungary's previous dominance, Märcz knows competition at the upcoming tournament -- led by favorites Serbia -- will be fierce.
"It's very difficult now in international water polo because at this moment there are a lot of very good teams," he says.
Since their first victory in the 1936 Olympics, the heat has beeen on Hungary players like Balázs Erdélyi.
"There are a lot of expectations," he says. "The media and the people on average expect us to get a gold medal every time, so it's big pressure on us."
His teammate Decker, however, says the pressure is an added incentive.
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"When I play in the water and I just look around and see 8,000 people, some people feel pressure," he says, "but for me it's a motivation and it gives me big energy in the hardest moments."