The Spanish club say they have not received any formal bids for the striker from City.
Emery said: "The most likely situation is that he will leave.
"It's possible the club can't reach an agreement for him, but we are prepared, we have spent some time working on alternatives.
"Of course we're not going to find a player with the same characteristics as him or one who is going to have the same record.
"But we will find players who will be important to the future of this club and I trust the work the club is doing in that area."