Hamano grabbed his arm after practice and then left the field with the team doctors.
Japan has been one of the teams that have impressed the most during the World Cup in Australia and New Zealand. So far, the Japanese have won all four of their matches, including beating one of the gold favorites, Spain, 4–0 in the group stage.
For Hamano, however, the World Cup debut has been a long time coming, the striker has not yet been substituted in any match.
Sweden meets Japan in Auckland on Friday.