The football insider is reporting on Twitter that the Red Devils have completed a deal to add the Brazil international to their squad in the summer transfer window.
Giulianelli has claimed that Manchester United won’t announce the deal for another fortnight when the versatile midfielder returns from his summer break.
Fabinho played a key role in the Monaco team as they won the Ligue 1 title ahead of Paris Saint-Germain and reached the Champions League semi-finals.
Manchester United have already completed the signing of Sweden international Victor Lindelof from Portuguese champions Benfica on Saturday afternoon.
And Serie A expert Giulianelli has claimed that Manchester United are set to confirm the signing of Fabinho from Ligue 1 holders Monaco in a deal worth around £40m (€45m).
Giulianelli wrote on Twitter: “Fabinho to Manchester United, done deal. Price €45mln, it will be official in two weeks, because he is on holiday. #MUFC #Transfers”
Fabinho scored 11 times in 55 games in all competitions during the 2016-17 campaign.
Manchester United won 2-0 against Ajax in the Europa League final to secure a return to the Champions League.
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