A groin problem forced the in-form Gundogan off against Tottenham Hotspur at the weekend and whilst his condition has improved, the City boss says he is likely to miss the game at Goodison Park.
However, there is better news regarding De Bruyne, who is back in full training after recovering from the injury he picked up against Aston Villa last month.
“[He’s] getting better,” said the manager at his pre-match press conference.
“Really getting better. Today he did all training with the group, with all of us. He’s much better.
On Gundogan, he added: “Gundo is much better, but I don’t think is available for tomorrow.”
The defender missed the FA Cup win over Swansea City last week due to illness and was an unused substitute against Spurs.
“Sergio is one year injured so cannot start from the beginning,” added Guardiola.
“But he is ready to come back. He was on the bench last game and will be again.
“The rest of the players are OK, except Nathan Ake.”
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