The striker has only trained with his City team-mates twice since arriving on Friday but Ranieri said he is toying with the idea of handing him a full debut.
"He is ready to play, but I will choose tonight who is the first 11," said Ranieri at a press conference at Club Brugge's Jan Breydel Stadium.
"For this reason I want to take my decision at the end because maybe we can start him at the beginning and when I see him a little tired I can change.
"Or maybe he can come with me on the bench and when I need him I can put him on during the match. I have to realise very well what I want to do."