The Belgium international looked certain to confirm his decision to leave Old Trafford upon the expiration of his contract next week, having failed to agree terms despite receiving several lucrative offers and Jose Mourinho publicly on record stating his desire to keep hold of the former Everton midfielder.
After months of speculation, however, Fellaini is will pen a new deal, turning down interest from the Chinese Super League, as well as Turkish and Italian clubs.
Having previously resigned himself to losing the 30-year-old, Mourinho had grown concerned about the lack of height and physicality in this midfield, according to Yahoo Sports.
The United boss had identified West Hams versatile forward Marko Arnautovic as a possible replacement for Fellaini but will now drop his interest in the Austria international who had been valued at £50m.
After securing the signings of Brazil international Fred and former Porto right-back Diogo Dalot, Mourinho is said to be keen on strengthening his defence and midfield still further.
United have been linked with a move for Lazio star Sergej Milinkovic-Savic but have been put of by the Serie A sides £100m valuation and have been linked with a number of A-list central defenders, including the likes of Toby Alderweireld, Jerome Boateng and Leonardo Bonucci.
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