A strike in the 56th minute from Luis Alberto stunned the hosts, and though the 70-year-old admitted his team should have got a better result, he was satisfied with the performance of an under-strength side.
"It was a wonder-goal that beat us," he told Sky Sports. "We didn't deserve that. We had a lot of chances. With a goal like that, you have no complaints, you can't do anything about it.
"We had a very young side out, they did very well at times. The pitch was a bit dead, there was frost on it. But I was satisfied we put a decent performance in.
"It was a decent experience for a lot of them. Young [Nick] Powell did quite well for us, he's only 18 years of age. Phil Jones, an excellent game for him tonight. It's only really his second game for us in about nine months, so I'm very pleased with that.
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"We qualified comfortably, there's no question about that. The real tournament starts at the end of February in the knockout stages - it's fantastic."
However, there was one sour note for the United boss, with Tom Cleverley departing the field just before half-time and Paul Scholes replacing him.
Ferguson afterwards revealed that the midfielder was suffering from a calf injury, the severity of which is not yet known.