National team coach Takeshi Okada is concerned about the fitness of the European-based duo.
According to reports in Europe, Inamoto, who plays for Eintracht Frankfurt, plans to undergo surgery this summer.
Nakata, currently of FC Basel but due to return to Kashima Antlers this summer, is recovering from surgery.
Okada has already announced that he will be requiring the services of Celtic midfielder Shunsuke Nakamura.
Nakamura is expected to miss the game with Ivory Coast on May 24 as the 29-year-old will return to Japan only after completing the Scottish Premier League season on May 22.
On June 2, the team takes on Oman on matchday three of 2010 World Cup qualification. Japan sit in second place with three points from two games.