The Champions League winners lost 2-1 to UEFA Cup holders Zenit St Petersburg, and they also lost midfielder Paul Scholes to a red card for two yellows.

The midfielder will now miss United's first Champions League game against Villarreal on September 17.

"The sending off was unfortunate, it was an instinctive thing," said Ferguson.

"The fact he had already been booked meant he had to go, unfortunately.

"We understand that he misses the first game in Europe, which is even more unfortunate.

"I cannot deny that Zenit deserved to win the game. I think that they probably just shaded is a little from us."

Goals from Pavel Pogrebnyak and Danny earned the well-organised Russian champions a two-goal lead which was halved by a Nemanja Vidic goal 17 minutes from time.

But Ferguson admitted his side had a few difficulties on a humid night in Monaco, particularly in defence, where Patrice Evra was run ragged by Zenit wing-back Aleksandr Anyukov.

"The one thing that kept them going was that they had three occasions when they got to the byline in the first 20 minutes and that was a concern for me," explained Ferguson.

"I was obviously looking forward to half time to eradicate that, which we did in the second half.

"I think in tight games, who scores the first goal is in a good position and conceding the first goal right on half time was a bad goal for us.

"There was not much in it and we congratulate St Petersburg on the victory."

Ferguson was happy with his side's reaction to going two behind, though.

Vidic's goal capped a strong period of pressure, led by the lively Carlos Tevez and the arrival of substitutes Ji-sung Park and John O'Shea.

The South Korean started to pull the Zenit defenders around a little and create openings for his team-mates and Ferguson was full of praise for his contribution.

"It's his first game for three or four months and his first step forwards after his knee operation," he said.

"I think with Ji-sung Park you get a good player with a good understanding of the game, good movement and he did his job okay.

"We played better when we were 2-0 down and made some good chances and when we scored with something like 17 minutes to go, we still found time to recover and get back into the game.

"But the game was running away from us a little bit."