Morocco began their Group D campaign with a 2-2 against Honduras on Thursday, while Japan began with an incredible 1-0 success over Spain.
The pair will meet on Sunday, with Japan knowing that three points should be enough to book their spot in the next stage of the competition.
This is the seventh Olympic tournament that Morocco have entered, but they have only reached the second round of the competition once.
Meanwhile, Japan secured the bronze medal at the 1968 Olympics and will be looking for a similar run this time around.
The Japanese also enter the match having won all three games in Great Britain since arriving two weeks ago.
Morocco will have to make an enforced change following the sending off of Zakarya Bergdich, with Abdelhamhid El Kaoutari likely to come into the side.
Meanwhile, Japan have a concern over goalscorer Yuki Otsu, with Takashi Usami on standby should the striker fail to recover.
Possible lineups:
Morocco: Amsif; Noussair, El Kaddouri, El Kaoutari, Jebbour; Kharja, Fetthoui, Labyad, Barrada, Bidaoui; Amrabat
Japan: Gonda; Tokunaga, Hiroki Sakai, Yoshida, Suzuki; Ogihara, Higashi, Yamaguchi; Otsu, Nagao, Kiyotake
Sports Mole says: 0-2
