Borussia Dortmund midfielder Shinji Kagawa is an injury doubt for Japan's World Cup qualifying warm-up against Oman in Kashima on Friday.
Kagawa trained separately from the main group after arriving back in Japan and skipped Wednesday's session because of a sore right ankle, although he did start Thursday's practice.
"Shinji Kagawa came back to Japan nursing a bruise and he has been training and continuing to get treatment. I will take a look at him tomorrow and make a decision then," coach Vahid Halilhodzic told a news conference on Thursday.