A star for England at the World Cup, Maguire is now said to be keen on the move and that could yet save a window for Jose Mourinho that has been described as “chaos”.
The Portuguese has been insistent since the very start that he wanted an authoritative centre-half alongside four other signings.
While Alderweireld has long been the main target due to his experience, the toughness of Tottenham's position has meant United consistently looking to other targets.
Some sources also maintain that Mourinho himself has changed his mind on possible options but with just hours of the window left, Maguire is considered the most viable alternative to Alderweireld.
There has long been an expectation the deal for the Belgian will eventually get done but there was still no sign of an official United bid on Wednesday night.
Although Alderweireld’s father had flown to England to advise in the event of any potential sale, the Spurs defender’s camp were on Wednesday night not overly optimistic of completing a deal. That could now open the door for Maguire, but United will still press ahead for the Belgian.
Bayern Munich’s Jerome Boateng has not been completely ruled out by those close to the United hierarchy, while some reports from France suggested Mourinho’s former Chelsea defender Kurt Zouma was an option. Jose Gimenez is considered too difficult to prise from Atletico Madrid.
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