There are plenty of supporters agreeing that N'Koudou was the right substitution, although he didn't actually do anything while he was on the field, but that dele Alli should have come off rather than Christian Eriksen.
There is an argument both ways. It isn't a question of who was playing better but of who is more likely to score a goal and with Eriksen's appalling shooting that was likely to be Dele Alli.
Despite his goal at Chelsea, Eriksen's shooting has been poor, it has generally all been at the centre of the goal lately, straight at the goalkeeper game after game.
Dele Alli didn't have a great game, but if you are trying to create and you give the ball away that isn't as bad as not trying to create at all. Simply passing to keep the ball wins nothing, at some point someone has to take a risk and if Dele Alli has the bottle to try and make the passes Eriksen so frequently fails to try then he is the one who should remain on the field. You can't have it both ways. Eriksen is just too content to keep passing going nowhere. They guy needs to take some responsibility.
dele Alli makes the runs into the box that Christian Eriksen doesn't and it is up to the other players to spot those runs and play him in. How many times did Eriksen touch the ball inside the Manchester United penalty area? He was moved to play central but it didn't make any difference.