During Monday's session, the workout was ended abruptly following Keita's retaliatory challenge on one-time Germany international Demme.
Bayern Munich new boy James Rodriguez is looking forward to facing his "amazing" former teammate Alvaro Morata in Singapore on Tuesday.
Earlier this month, Dortmund said they were no longer open to the possibility of selling Aubameyang.
Bayern Munich are not entirely happy with their current 12-day tour of Asia and will put the format "up for discussion" when they return to Germany.
Newcastle United are lining up a move for RB Leipzig goalkeeper Peter Gulacsi, sources in Germany have told ESPN FC.
Jurgen Klopp has told the Mirror he is unsure whether his Dortmund "story" would be possible now, saying: "They gave me the time to do something."