Manchester City boss Pep Guardiola has confirmed Sergio Aguero will undergo knee surgery in Barcelona tomorrow.
City's record goalscorer limped off shortly before half-time during Monday's Premier League victory over Burnley at the Etihad Stadium.
No timescale has been put on the striker's return but he has not yet been ruled out for the Champions League resumption in August.
Guardiola said: "Tomorrow he is going to make a surgery. Once he has finished the surgery we will know the time Sergio will come back to play with us."
Asked at a press conference if Aguero would be back for the Champions League games, Aguero said: "I don't know right now."