Ryohei Yamanaka trained with the Japan Rugby World Cup squad for the first time Wednesday in Monaco following his call-up to replace Semisi Masirewa.
Masirewa hobbled off the field in the seventh minute of Sunday's 34-12 defeat to England and was ruled out for the rest of the tournament the following day. The Japan Rugby Football Union did not disclose his exact injury.
Yamanaka, seen by many as unlucky not to have made the original 33-man squad, was in Europe with the British-based Barbarians squad, and flew in to join the team on Monday night.