Pep Guardiola was forced to field a makeshift line-up with plenty of youngsters and players who spent last season out on loan, with 16 senior players still to join up for preseason after playing at the World Cup.
A number of City's stars are absent for the pre-season fixture following the World Cup in Russian Federation.
The Citizens are still reeling after losing out on Jorginho to Chelsea, having long thought that the Italy worldwide wanted to move to the Etihad Stadium.
"I was disappointed (not to sign him)", he added.
"It would have been a mistake for him if he came and he wanted to go to Chelsea with Maurizio Sarri".
"My advice for all players is they have to go where they want to go, and in the end it would have been a mistake for him and for us if he'd chose to come here when he wanted to go with Maurizio and Chelsea".
"So it is important that English football has received an exceptional player and at the end if they want to come, it's better they come".
But one player who will be involved against Dortmund is out-of-favour goalkeeper Joe Hart.
Former England goalkeeper Joe Hart, meanwhile, is poised for some surprise playing time in the U.S. having returned to the club from a loan spell at West Ham United.
And while Die Mannschaft suffered a humiliating first-round exit, Guardiola has offered some advice to the 22-year-old, as they prepare for the 2018/19 season. "We tried but players have to go where they go".