"A further announcement will be made in due course", is how the Red Devils ended their statement, but Fred is a Red and that's nothing but good news for the club.
Alternatively, Mourinho could choose to use Fred in a more conservative role alongside Matic in a two-man defensive midfield screen.
The Brazil squad, now preparing for Sunday's friendly against Austria at Tottenham's Enfield Centre, were quick to congratulate Fred on Tuesday after his move was confirmed. They will kick off their campaign against the South American side on June 15, before facing Russian Federation and Saudi Arabia respectively.
The Manchester United boss has tipped the Three Lions to top Group G - where they would be paired with Poland should Mourinho's premonitions come true.
How will his arrival impact Paul Pogba's future?
They can tackle, pass, dribble and score the odd goal, but there are differences in their styles.
Fred, meanwhile, is more of a powerhouse, who looks to commit opposition midfielders through driving runs upfield. They have experience, top players, right mentality. Darmian has been linked with Juventus and Blind is a target for Inter Milan.
"Man United fans have been brought up on a tradition of playing the game in a certain way".
Anything else we should know about?
The 25-year-old completed his deal to move to Old Trafford from Shakhtar Donetsk yesterday (Tuesday) after successfully completing a medical earlier in the week.
Fred was handed a two-year ban between July 2015 and July 2017 after he tested positive for the diuretic hydrochlorothiazide during Copa America.