The English club's new coach, Erik ten Hag, has joined from Ajax and is now bringing in 24-year-old Lisandro Martinez.
Ajax have confirmed the amount that Manchester United pays, a sum that can exceed SEK 700 million with certain bonuses.
The only thing missing is the mandatory medical examination for Martinez before the personal contract can be signed with Manchester United.
He then joins a squad where established midfielders Victor Lindelöf, Harry Maguire, Raphael Varane, Eric Bailly and Phil Jones are housed.