However, they may now have to accept paying an inflated price to get the defender Mourinho craves before the transfer window slams shut on Thursday night.
Manchester United manager Jose Mourinho is a known admirer of Alderweireld's and the clubs CEO Ed Woodward has been trying to broker a deal for the defender since May.
Everton appear to be edging ever closer to completing the signing of Yerry Mina from Barcelona. And it seems like Tottenham are ready to cash in on Toby Alderweireld now. Mina's adviser, Felipe Russo, "angered" United by constantly demanding increased payments.
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Leicester City refuted United's enquiry, with Maguire a genuine second choice; and Mourinho's frustration on the recent tour of the USA was visible to all to see.
That meant less game time for the 29-year-old.
However, The Sun are reporting that Mina's agent, Felipe Russo, has scuppered the proposed move to United by altering the terms of the deal. The towering defender is regarded as one of the best in his position in the Premier League, despite going through a hard 2018-19 season.
Mourinho has cut a frustrating figure all summer due to the lack of progress in the transfer window. Far more than Yerry MIna would cost but experienced in the Premier League.