Arsenal's Takehiro Tomiyasu and Urawa Reds Diamonds' Hiroki Sakai both sat out of the Blue Samurai's 1-0 defeat against Costa Rica on Sunday with minor hamstring injuries, and the defensive pair are both doubtful for the clash at the Khalifa International Stadium.
Meanwhile, midfielder Wataru Endo picked up a knee problem in the closing stages of last weekend's loss and has since missed training with the first-team squad.
The 29-year-old Stuttgart man has emerged as a major doubt and is likely to be replaced in the middle of the pitch by either Ao Tanaka or Gaku Shibasaki.
A back four of Miki Yamane, Ko Itakura, Maya Yoshida and Yuto Nagatomo is set to remain intact, shielding first-choice goalkeeper Shuichi Gonda.
Eintracht Frankfurt playmaker Daichi Kamada is the only attack-minded player who has started both of Japan's first two group fixtures, and the 26-year-old is expected to operate again in the number 10 role in behind either Ayase Ueda or Daizen Maeda.
Ritsu Doan and Takuma Asano, who both scored in the shock 2-1 win over Germany, will be competing with the likes of Takefusa Kubo, Yuki Soma and Junya Ito for a place on the flanks.
Japan possible starting lineup: Gonda; Yamane, Itakura, Yoshida, Nagatomo; Tanaka, Morita; Doan, Kamada, Kubo; Maeda