Louis van Gaal is desperate to strengthen his defence but has thus far been thwarted in his efforts to land any of his top targets.
United maintain that they will not consider stop-gap options this month, seemingly scuppering a move for the likes of Nemanja Vidic.
But both Hummels and Laporte fall into the category of long-term investments and United and reports suggest that the Old Trafford outfit have not given up hope of luring at least one of the pair to England in the coming days.