The 23-year-old, who played in the Dutch club’s run to the Champions League semi-finals last year, has entered into a five-year deal with the option of an additional 12 months.
And Rashford is clearly happy with the situation after he “liked” a tweet in which reporter Fabrizio Romano claimed the Red Devils were confident to land Van de Beek.
The England forward isn’t the only United player ready to welcome Van de Beek to Old Trafford, with January signing midfielder Bruno Fernandes also liking an Instagram post announcing the news.
United beat some of Europe’s top clubs to land Van de Beek, with Real Madrid and Barcelona showing interest in the midfield.
The Netherlands international, who has scored 41 goals and provided 34 assists in 175 games for Ajax, appeared bound for Madrid earlier this summer when the Spanish champions agreed to a fee of £ 44.6million.
But the deal fell apart when the coronavirus crisis hit.
New Barcelona boss Ronald Koeman has also said he wants to take the midfielder to Camp Nou, but the Catalan club are in turmoil after Lionel Messi’s bombshell he wants to leave.
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Van de Beek has told friends in Amsterdam that manager Ole Gunnar Solskjaer’s determination to sign him was the key factor in his decision.
He was impressed with the vision the United boss described to him on the direction the Red Devils are taking after finishing third last season to seal a return to the Champions League.
Van de Beek declined to play in Ajax’s friendly against Eintracht Frankfurt on Saturday after learning United were preparing to boost their interest with an official offer.