The Samurai Blue cruised past Guatemala but will face a sterner test against Kwesi Appiah's men, who sealed a place in round three of Africa's qualifying section on Friday
Kwesi Appiah's side went into the crucial match in Kumasi one point ahead of their visitors knowing that anything other than a defeat would take them through to the third stage of the CAF qualifying section for Brazil 2014.
Ghana, whose only defeat in Group D came in the reverse fixture against the 2012 Africa Cup of Nations champions, secured a narrow 2-1 win as Abdul Waris and Kwadwo Asamoah gave them a two-goal lead before Emmanuel Mbola pulled one back for the visitors.
But, while Ghana have another stage of qualifying to go through to seal their place in next year's showpiece, Japan were the first side to reach Brazil after their 1-1 draw with Australia on June 4.
Japan's latest fixture came in a friendly against Guatemala at Nagai Stadium on Friday, goals from Keisuke Honda, Masato Kudo and Yasuhito Endo sweeping aside Sergio Pardo's side, with coach Alberto Zaccheroni afterwards calling on the team to keep up their level of intensity in their next matches.
"We put good pressure on our opponents, particularly in midfield, while keeping our back line high. Our forwards pressed their opponents well, too, which kept Guatemala from moving upfield," he observed.
"I hope we can continue doing that against other, high-ranked opponents in our upcoming games."
His Ghanaian counterpart, Appiah, was also in a content mood after his team's vital victory over Zambia.
"We needed to either get a win or get a draw and the most important thing our aim was to try and get a win which I think the players did very well," he explained. "Zambia have got a very good team and it was not going to be easy game and we saw that."
Since earning qualification for the World Cup, Japan have been inconsistent as they have beaten nations such as South Korea, Australia and Iraq, but succumbed to three losses at the Confederations Cup.
Ghana, on the other hand, have lost only twice in their last nine matches.