Frenchman Philippe Troussier, who led Japan to the last 16 as co-hosts of the 2002 World Cup, told Reuters on Tuesday that the team had a "stupid mentality." Okada was confused and recommended wholesale changes.
Okada, who said he had offered his resignation after the defeat in Saitama on Monday, said he was sticking to his plans after the squad's first training session at a training camp in Saas-Fee, Switzerland.
"I think this team is what it is," he told the Kyodo news agency.
"Sometimes you are going to have players injured or out of condition or unavailable or whatever but I have no intention of making any major changes to what we have been doing.
"I still think this is a team that is capable of going places. The most important thing is to keep repeating what we have been trying to do until now."
Next up for Japan is a friendly against England in Austria followed by their final warm-up match against Ivory Coast on June 4th back in Switzerland.
Japan play their Group E opener against Cameroon on June 14th and also face the Netherlands and Denmark in the first round of the tournament in South Africa.
