The former Real Madrid winger will come up against a number of his Argentina international team-mates on Sunday but insists when on the pitch those relationships are forgotten
The British-record signing will face Argentina team-mates Pablo Zabaleta, Martin Demichelis and Sergio Aguero at the Etihad Stadium as he looks to help the Red Devils to their first away win of the season.
The former Real Madrid star has found the net three times since moving to Old Trafford, and though he admits he will acknowledge his fellow countrymen in the tunnel, their relationships will have no impact on the game.
"We’ve got good friendships over the years and no matter what the colour of your shirt, you still see each other socially," he told reporters.
"But once you’re on the field, you forget all that. Everyone is fighting for the shirt."
"When we see each other in the tunnel before games, I think it’s right to say ‘Hi’ and greet each other – whether it’s an ex-team-mate or a good friend.
"That’s normal, as long as you remember that you fight for the club and the shirt once the 90 minutes start."
Goal revealed on Friday that the 26-year-old could have signed for Manchester City had Financia Fair Play restrictions not halted them, with Manuel Pellegrini also revealing the Premier League champions could not afford to pay €76 million for his services.
Di Maria, though, admits that he was unaware of any interest from the blue side of Manchester, while none of his international compatriots tried to convince him to sign for the club.
"No, there was never any contact anywhere else. The people who came with all the paperwork, signed and ready, showing real eagerness to sign me were United," he added.
"As soon as I heard of their interest, there was no question of me going anywhere else. As a player, you’re always going to go somewhere if the club really want to sign you and show willing by putting that amount of money on the table."