The Daily Express says bitter rivals Manchester United were originally pursuing Hummels, and they had sent scouts to watch him play, but interest on their part appears to have cooled in recent weeks.
But Roberto Mancini is still worried about the soft goals City are conceding, as they try to chase down United in the title race.
Hummels appears to be keen on a move to the Premier League, having originally said: "One day I will say that I am keen on a transfer.
"To play football in a new country would be flattering. I already had offers and one enquiry from these offers was really one of interest for me."