Akira Nishino may only have one game in charge of the Japanese national team before he decides on the squad to take to the World Cup in Russia, but that isn't stopping him from possibly making significant changes to his line-up.

Under former boss Vahid Halilhodzic, who was replaced by Nishino in April, the Blue Samurai played four across the back in their successful qualification campaign for next month's tournament. However, the new boss wants to introduce a three man defence for Wednesday's home friendly against Ghana.

The formation is likely to resemble a 3-4-2-1, with two attacking midfielders supporting the lone striker and full backs expected to contribute in defence and attack.

Nishino said he was keen to see whether his tactical experiment would be the one to go with for Japan's World Cup opener against Colombia on June 19.

"Through the process of trying it in tomorrow's match, I want to identify the best way to fight against Colombia, whether it is with three centre backs or four," Nishino told reporters on Tuesday.

"We need to choose the base formation and having (either) three or four at the back will be chosen to give us the most realistic chance of fighting Colombia."

Nishino will announce his World Cup squad on Thursday, leaving little time to analyse the game against Ghana and decide on the 23 players he wants to take to Russia.

"After fighting 100 percent in tomorrow's match and thinking about various things then I will need to choose the squad on the morning of the 31st," said Nishino.

"My suffering or worrying will continue."

KAGAWA FEELING FIT

Nishino is also looking to pair Shinji Kagawa alongside stalwart Keisuke Honda as attacking inside forwards, supporting Leicester City's Shinji Okazaki in attack.

Kagawa, who has only played 15 minutes of soccer for his Bundesliga side Borussia Dortmund since February due to injury, did train with the rest of the squad on Tuesday.

"I have been playing without any worries but I must verify and prove this on the pitch," said the former Manchester United playmaker.

The 29-year-old was also quick to stress the togetherness of the squad under Nishino, who had been brought in after a difficult period under predecessor Halilhodzic.

"With the new coach, I am having a fulfilling training camp, from the very first day," said Kagawa.

"The team atmosphere is also really good so I am very excited about tomorrow's game."

Nishino's men also face Switzerland and Paraguay in friendlies before they head to Russia.

As well as Colombia, Japan will also take on Poland and Senegal in Group H at the World Cup.