Argentina boss Gerardo Martino believes that Manchester United signed Angel di Maria "on the cheap" this summer.

United paid Real Madrid in the region of £60m for the attacker in the summer transfer window and the figure was questioned in some quarters.

However, Martino believes that the former Premier League champions were right to pay such a figure for a player that has already scored three goals and registered three assists in five games for United this season.

"I think that the club directors got him on the cheap because he is such a versatile player – he can adapt to any position on the field, on either wing or through the middle. Angel is one of the most relevant players that Argentina have had in recent years," Martino told reporters.

Di Maria is in the latest Argentina squad for the upcoming friendlies against Hong Kong and Brazil.