Japan coach Zico wants the Asian World Cup qualifying format changed in order to protect top teams from missing out.

The Asian champions play Oman away on Wednesday and, while a draw would see Japan through to the final round of qualifiers, a defeat could mean they crash out.

"I think they should change the current format so you don't get a situation where the traditionally strong teams are at risk of not qualifying," said Zico.

"Japan are good enough to be in the World Cup finals. The World Cup needs teams like Japan as well as China, South Korea and Saudi Arabia.

"The rules should be changed to protect the teams that have done the most for Asia."

However, Zico's plea ignored the fact that Japan have qualified just twice for the World Cup -- the second time as co-hosts in 2002. China have only qualified once.

South Korea have been to six World Cups and reached the semi-finals as co-hosts with Japan two years ago while Saudi Arabia have qualified three times.

Japan struggled to beat Oman at home in their opening 2006 qualifier in February and at the Asian Cup in July.

They lead Oman by three points in Group Three and defeat in Muscat would leave Japan in a precarious position with one game left to decide who advances.

Only the top team from each of the eight groups goes through.