Unstoppable Bayern Munich forward Robert Lewandowski scored a hat-trick, taking his tally to 10 goals in five Bundesliga games, as the defending champions thumped hapless Eintracht Frankfurt 5-0 on Saturday.
Ajax Amsterdam gave coach Martin Jol a winning start with a 2-0 success over Groningen in their opening game of the new Dutch league season on Sunday.
France international Dembele scored 10 goals and provided 20 assists in all competitions to help Dortmund finish third in the Bundesliga last season. The team also won the German Cup.