Ferguson is now considering who will start in goal when United face Wigan after the international break.
He said: "In goal, it was a big decision but I thought David De Gea lost a bad goal last week.
"He has to learn quickly and he'll be back with us after the international break but Anders (Lindegaard) had his first game.
"I thought he was a little bit nervous at points but he's also a very good keeper.
"I don't think it's a big issue but it's something you have to deal with."