Yes, Erik Ten Hag's mistake was when he threw De Gea out of the squad and replaced him with Onana. Onana was brave enough to be brought to Old Trafford because of his impressive performance with Inter, but unfortunately for United he always made mistakes that were detrimental to his team. Not only Onana, several other players must also be evaluated for the good of the team. I don't know how long Erik Ten Hag will stay at Old Trafford, if he doesn't get better maybe he will soon be asked to leave because the club has spent a lot of money to build the squad.
MNU new goalkeeper is waste of money and time. Local sportbet service near me found out that Onana have negative save ratio and this is for last week or something like that. He saved 4-5 on goals shoots but received 12-13 goals in 18-19 shoot on target, That is very low for goalkeeper of this caliber you will all agree.