Playmaker Kevin De Bruyne, forward Gabriel Jesus and defenders Aymeric Laporte and Nathan Ake all missed Wednesday’s 3-1 Champions League win over Porto.

City then received another blow when midfielder Fernandinho was ruled out for up to six weeks after suffering a leg injury late in the game.

“I think we’re struggling at the moment,” Gundogan told BT Sport.

“Fernandinho went off in the last minute. We have a few injured players. We have players in different conditions. Even me, I’m not 100% yet because I was out with Covid.

“We’re all in different moments. It’s the challenge this season and it’s not going to end for a while.

“It’s not going to be difficult for Pep to choose the 11 because some players will be tired, they can’t play every game, others need to play,” Gundogan added.

“Obviously, we’re glad we have a big squad but not everyone is there yet and not everyone is at 100%.”