Real Madrid beat city rivals Atletico but racist chanting directed at Vinicius Jr outside the Metropolitano marred the derby.
It was an unhappy return to Munich for Barca striker Robert Lewandowski, the Bavarians' second-highest all-time scorer, who left under a cloud in the summer.
Mathys Tel became Bayern Munich's youngest goalscorer but Stuttgart earned a late 2-2 draw in the Bundesliga on Saturday.
Raphinha scored his first Barcelona goal as the Catalans beat Sevilla. Also: Real Madrid and AC Milan won but Bayern Munich had to settle for a draw.
Chelsea sign former Arsenal striker Pierre-Emerick Aubameyang from Barcelona with Marcos Alonso going the other way after his Blues contract was terminated.
New-look Marseille's bright Ligue 1 start continued as Alexis Sanchez's double lifted them within goal difference of leaders PSG, who were held at Monaco.