Manchester United are already planning for the next transfer window, as they eye a move for Argentinan teenage sensation Franco Mastantuono. It was a very busy transfer deadline day for Erik Ten Hag’s Manchester United. The Red Devils secured the long-awaited signing of Manuel Ugarte, whilst also sanctioning the departures of Scott McTominay and Jadon Sancho. With the window slamming shut on Friday evening, the United boardroom are seemingly already putting plans in place for January as they line up a move for River Plate’s Franco Mastantuono. That is according to Marca, who revealed on Sunday…