The 21-year-old is regarded as one of the most exciting young players in European football and was heavily linked with a move to Barcelona or Manchester City over the summer, though opted to continue his development in Amsterdam.
De Jong is an incredibly versatile player who can play either in midfield or defence, though has predominantly lined up in central midfield so far this season.
According to Dutch newspaper De Telegraaf, United have made contact with De Jongs agent to register their interest – though they face significant competition for his signature.
Real Madrid see the youngster as the ideal successor to Luka Modric, and would be prepared to pay Ajaxs £71.5m asking price next summer – a fee United would need to match.
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The club were adamant that he would not be allowed to leave this year, but are more relaxed about letting him move to a European giant in the future.
Ajax director of football Marc Overmars is said to be licking his lips at the possibility of a bidding war, with PSG, Bayern Munich and Tottenham Hotspur also showing interest alongside United, Real and Barca.
De Jong has the best passing accuracy of any player at Ajax, while he also averages the most passes (84) per 90 minutes of any player in the Eredivisie.
The youngster has won two caps for his national team, and any fears that £71.5m might be too steep for a relatively inexperienced player have been allayed by incredibly positive scouting reports.
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