Woodward tendered his resignation in April following support for the ill-fated Super League and the expectation had been Arnold would succeed him.
Arnold said: “I am honoured to have the chance to serve this great club and its fans. I am determined to return that honour in any way I can.”
The United co-chairman Joel Glazer added: “I would like to thank Ed for his tireless work on behalf of Manchester United during his nine years as executive vice-chairman and 16 years with the club.
“We are now looking forward to Richard and his leadership team opening a new phase in the club’s evolution, with ambitious plans for investment in Old Trafford, the strengthening of our engagement with fans, and continued drive towards our most important objective – winning on the pitch.”
Meanwhile, it’s understood United have no plans to sign River Plate’s Julian Alvarez this month.
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