Brotherly love will be put aside when Samoa meet Japan in their opening Pool D match tomorrow. For the first time in World Cup history, brothers Stephen and Graeme Bachop will line up on opposite sides - Stephen for Samoa and Graeme for Japan.

"It's a unique situation as far as the World Cup is concerned," Stephen Bachop said. "A year or two ago who would have thought we'd both be playing at the World Cup against each other? It's a big day."

The Bachops, both former All Blacks, spoke to each other by phone this week but it was mainly on family pleasantries.

Stephen Bachop admits Japan's foreign legion will severely test them.

Apart from brother Graeme, Japan boast four other New Zealanders, Andrew McCormick in the midfield and Jamie Joseph, Rob Gordon and Greg Smith in the pack. Joseph and Gordon are also former All Blacks.

Japan beat Samoa in the Pacific Rim tournament this year with a late try by Joseph and that is all the reminder Samoa needs of possible problems in Wrexham.

"All those Kiwi guys have added a lot of experience, direction and size to the Japan team and the Japanese players themselves are very fit - they never lie down," Stephen Bachop said.

"They just kept coming back at us in the Pacific Rim."

Japan won this year's Pacific Rim but Stephen Bachop is confident Samoa can gain revenge.

"If our front five can produce the goods, I think we can do some damage at this tournament," he said.