Liverpool goalkeeper Alisson and forward Diogo Jota face spells on the sidelines because of injury.
Manager Jurgen Klopp says Alisson's injury is not as bad as first feared but he is still set to be out for about two weeks, while no timescale has yet been put on Jota's recovery.
"Both are out," said Klopp. "With Ali it's a bit lesser, so we have to see."
Portugal international Jota was forced off after 54 minutes at Etihad Stadium, while Alisson completed the game despite sustaining hamstring injury late on.
Asked about Alisson's injury not being as bad as first feared, Klopp added: "No, but bad enough.