The 23-year-old is a key member of Mauricio Pochettino's impressive Tottenham team.
This season Dier's versatility has allowed Pochettino to field a 3-4-3 formation which seen him deployed alongside Jan Vertonghen and Toby Alderweireld.
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Tue, March 28, 2017
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John Terry – 100/1
Dier is also a regular for the England team and has set his sights on captaining his country.
But at club level, according to The Sun, Mourinho is keen to make Dier a part of his summer squad overhaul.
Tottenham midfielder Eric Dier
It is claimed the United boss has been allocated the funds to build a squad capable of mounting a credible challenge of trophies domestically and in Europe.
The report values Dier at over £40million.
Carrick, who has been at United since 2006, is out of contract in the summer and appears unlikely to be offered a new deal.