The country's best-supported side have launched "Project Eagle," which involves the use of falcons, to keep the web-footed invaders at bay.

"We have had problems with ducks for a while," Urawa's public relations chief Daisuke Maruyama said on Tuesday. "They leave their mess on the pitch.

"We've taken a number of measures to clean things up, including falcons and putting out cones on the pitch. The things you have to do sometimes!"

The team's training pitch was littered with hundreds of feathers and mounds of droppings on Monday with bite-sized chunks of grass nibbled off by the culprits.

Having lost their season opener 2-0 at champions Kashima Antlers at the weekend, Urawa manager Volker Finke was unamused at the mess left by the birds on arriving for training.

Urawa have been forced to conduct daily duck patrols with officials waving blinking torches to frighten off the visitors, identified as common dabbling ducks.

"It seems the ducks feel safe inside the fence which surrounds the training ground," said Maruyama. "But our measures look like they're slowly bearing fruit."