Manchester United have submitted a €60 million (£53m) bid to sign Fiorentina centre-back Nikola Milenkovic, according to reports in Italy.
Jose Mourinho clashed with Uniteds hierarchy over the need to sign a new defender this summer with his requests to sign Toby Alderweireld and Harry Maguire blocked by the club.
The United boss remains keen to reinforce his defence and has taken matters into his own hands during the international break as he personally watched Milenkovic in action during Serbias win over Montenegro on Thursday evening.
According to La Nazione, Mourinhos desire to sign Milenkovic is so strong that he immediately got in touch with Uniteds hierarchy after returning to Manchester.
And United have now put a €60m (£53m) offer on the table to Fiorentina ahead of the January transfer window.
United have also spoken to the 21-year-olds agent, who has indicated that the defender would be willing to move to Old Trafford.
Fiorentina, however, have rejected Uniteds bid and are keen to keep the Serbia international until the end of the summer as his price could increase even further.
Milenkovic has spent just over a year in Serie A but has already cemented his place as a first-team regular at Fiorentina.
The 21-year-old has also been compared to ex-United defender Nemanja Vidic by Serbia boss Mladen Krstajic.
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