Pep Guardiola claimed defeat by Basle should act as a warning to Treble-hunting Manchester City.
City, 16 points clear at the top of the Premier League, should wrap up the title in the coming weeks.
But Guardiola has told his stars that their levels cannot drop in the league if they are to achieve Champions League glory.
‘I know everyone wants to anticipate when we are going to win the title,’ the City boss said.