Sergio Aguero's knee injury means he will miss Manchester City's Champions League game with Porto.
Aguero was absent for Saturday's 5-0 win over Burnley with a knee problem and has not returned to training.
The 32-year-old Argentina striker has only played four times this season.
"I am not concerned. He did not train. He had a little disturbance in his knee. It is nothing serious," said boss Pep Guardiola.
City have already booked their place in the last 16 after winning their first four games. A draw in Portugal will seal top spot.
