The pick of the fifth round was expected to be a close affair but United were three up by half-time and Darren Fletcher rounded off victory with his second after 74 minutes.

Ferguson told MUTV: "It was a really fantastic performance. The players looked great. They showed tenacity and the passing was terrific.

"They were so disappointed with themselves (after losing 2-1 to Manchester City) on a really important day. I think all the emotions of the week probably caught up with them.

"But today they've made amends for that with a marvellous performance."

United ran the midfield, and Ferguson reserved particular praise for Fletcher, who has had little opportunity to shine this season.

"Darren Fletcher is one of these players who always plays well against Arsenal," he added on his club's TV station.

"I think he's had two man of the matches in semi-finals. Sometimes it's horses for courses and I think it was Darren's day.

"We decided to play three in the middle of the park to control things, which we did very well.

"Some of the passing was very good and the running off the ball was very good. It was a great performance by us."

Arsenal's cause was not helped by the sending-off of Emmanuel Eboue early in the second half for a high challenge on Nani.

But Ferguson felt Gunners defender William Gallas should also have seen red.

"I thought Gallas should have been sent off," the United boss said.

"The referee must have a look at that again. He kicked Nani from behind and the referee called both over because they sized up to each other. He should have been red-carded."

Arsenal seemed unhappy with Nani's apparent show-boating, and Ferguson admitted the Portuguese winger's tricks were somewhat unnecessary.

The Scot explained: "I agree, I think he shouldn't be doing that, he doesn't need to do that.

"In some ways it shows a great deal of courage to do what he did, that's one side of it, but you don't need to do that."

Arsenal have a five-point lead in the Barclays Premier League title race, but Ferguson hopes today's result could prove the turning point.

"I hope so, I really do," he added. "Who knows? You never know what position both clubs are going to be in but it's certainly whetted our appetite for future games."

The result was achieved without star man Cristiano Ronaldo, Ryan Giggs and Paul Scholes.

Ferguson revealed Ronaldo had a stomach upset while Giggs and Scholes were rested ahead of the Champions League meeting with Lyon on Wednesday.