"Teams often change their line-ups after qualifying for the next round. It is not clear at the moment how Brazil will do," Zico said as Japan resumed training here Monday, the day after they battled to a goalless draw with Croatia.

"But, even if they change their line-up, it won't make our life easier because of their potential," said the star of three of Brazil's World Cup campaigns.

"I can only say now that we are determined to challenge them no matter what."

In Group F, Japan must at least beat five-time World Cup holders Brazil to keep alive their faint hopes of booking the last of Group F's two tickets for the second round.

Brazil, boasting a galaxy of talents including Ronaldo, Adriano, Ronaldinho and Kaka, qualified for the knockout stages on Sunday by beating Australia who earlier trounced Japan.

"My players understand well that they are here to fight for their country and they must do their best as long as there is the slightest of chances left," Zico said. "I'd like to send them on to the pitch by reminding them of this."

Both Japan and Croatia trail two points behind Australia and they need to at least win their last group games on Thursday to stay in contention.

Then, goal difference will matter. As for Japan, they must beat Brazil by a margin of two goals, provided that Croatia defeats Australia by no more than one goal.

Zico, 53, who has been helping raise the standard of the Japanese game for 15 years first as a player, has categorically denied his Brazilian connection could help fix a result which ensures Japan of a place in the second round.

He told foreign reporters in Tokyo in April that such a deal, not unheard of in World Cup history, is a "shame for international football" and must be "properly punished."