Kosovar Asllani and her Real Madrid defeated national team colleague Filippa Angeldahl's new club Manchester City 1-0 in the return match away from home in the decisive Champions League qualifier and advanced to the group stage with a total of 2-1.
Asllani, who tested positive for covid-19 at the end of August, missed the first meeting at home which ended 1-1 and jumped into the end of Wednesday night's victory match in England.
The Olympic success Angeldahl, who was recruited from Häcken just under a week ago, was not in City's match squad.
Real's Zornoza Sánchez scored the only goal of the match in the 44th minute.
The group game will be drawn on 13 September.