FC Tokyo midfielder Shoya Nakajima has injured his right knee and will need five to six weeks to recover, the J. League first division side said Monday.

Nakajima, who is expected to play a key role on the Japan squad at the Rio de Janeiro Olympics this summer, suffered a ligament injury during a shooting drill at Friday's practice.

In January, the 21-year-old scored twice in extra time in Japan's 3-0 win over Iran in the quarterfinals of the Asian Under-23 Championship, and was later named the tournament MVP.