Moyes said: “We are gutted after being two up. We gave United a great opportunity to get back into the game.
“Not only did it hurt us, it gave them a massive lift at a period when we were comfortable. Playing against a very good side, we did a decent job.
“The keeper’s error was a big turning point in the game. If we had lost to United with their style and attacking ability, which is fantastic, I’d have said, okay.
“But we gave them two goals. If United had opened us up and scored brilliant goals, the way they can, I’d be the first to say it is hard to stop that.
“But we could certainly have done something to have stopped those goals. The first one certainly, and the second. We let the goal come across the box for their third and the fourth one could have been avoided by kicking the ball up the park, not giving it to them.
“For me, the goals were poor all round. I’m disappointed we made it easy for United in the end, they got a slice of luck but it was down to that first goal.
“I do not think they would have got back into the game had it not been for that first goal.”