Real Madrid had previously rejected a £52 million bid for the Spanish striker but now he's said 'yes' to a move, negotiations have begun over a fee.
A few complications remain where a transfer is concerned, though, one being the recent David de Gea saga.
According to the Mirror, Real are playing hard ball and demanding at least £60 million for Morata after United did the very same for De Gea.
Morata may have agreed to join United and told friends he expects to be playing at Old Trafford next season, but coming to an agreement is going to be far from easy it seems.
The 24-year-old has provided several hints over the past week about where his future lies, such as his recent following spree on Instagram.
Eagle-eyed United fans discovered Morata had followed the likes of Wayne Rooney, David de Gea, Paul Pogba and Juan Mata on the social media site.
It could have been mere coincidence, of course, but further evidence appears to have been provided that Morata will be leaving Real and joining the Red Devils.
United and Real fans also noticed on Friday night that Morata has removed 'Real Madrid player' from his Twitter bio to just read: "Perfil oficial de Álvaro Morata" (see below).
Morata has also removed 'Real Madrid player' from his Instagram bio.
It may have just been a mistake had Morata only changed one of his social media profiles, but he's clearly gone to the effort of removing 'Real Madrid player' from both Twitter and Instagram.
Exciting stuff - here's how Twitter reacted to Morata's social media activity.
The incentive behind joining United for Morata is clear. Following a season where he played second fiddle to Karim Benzema at Real, the Spaniard just wants more game time.
At 24-years-old, Morata still has plenty of room to grow, and with regular minutes and Jose Mourinho mentoring him, the sky is the limit.
From Mourinho's perspective, Morata represents the perfect replacement for Zlatan Ibrahimovic, who was confirmed as leaving United on Friday.
Ibrahimovic wasn't the fastest but possessed the strength and intelligence to score 28 goals in all competitions for United, which they will hope Morata can replicate.
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