The signing from PSG is in line to make his United debut today against Southampton.
Ten Hag told MUTV: “I played him already, as manager of Ajax, when we played Sporting Lisbon. He’s quite a long time on my radar. He’s coming in, it’s a late transfer coming in, but he’s playing in a very important position. You have to connect defending with attacking and attacking with defending.
"Communication is very important there, to tie the team, to lead the team, to make the connection between attacking and defence, defence and attacking. We have to help him, we have to guide him, how he has to play that role, but from what we have seen, he knows already a lot, of course. He has the profile where we think he can fit in that role and now we have to teach him some details, how it works in our team.
"It was not only that match but also in the seasons after, when he played there, when he played for Uruguay, when he played for Paris. I have him in my mind, I have him in my eye. The scouting department has him in their mind and we followed him. We judged that he would be a really good fit for our team.”