"I've got to be pleased with the possession and the concentration was really good tonight," Ferguson told ITV Sport. "Apart from the goal we defended very well.
"They hit so many really good, telling crosses into our box that kept us under pressure all the time, kept us on edge.
"David [De Gea] made a good save at the end so I've got to be pleased. Coming away from home in Europe is never easy and as I said before the game, they've a good record here."
United are now at the top of the group with two wins from two matches.