Japan defender Maya Yoshida has called for cool heads as the Asian champions prepared to leave Sunday for a high-stakes World Cup qualifier against Jordan in Amman.

Wary of what he describes as whistle-happy Asian referees, the Southampton center back has admitted he may have to "tone it down" in Amman, where victory for Japan on Tuesday would see it become the first team to qualify and join hosts Brazil in next year's finals.

"We have to have cool heads and I myself will need to tone it down and avoid making reckless challenges," said Yoshida, one of the few bright spots in Friday's unconvincing 2-1 win over Canada.