WHEN Barcelona overwhelmed Manchester United to win the Champions League two years ago, Sir Alex Ferguson said that his side had been beaten by the strongest team in the world.

“Great teams do go in cycles and they’re at the peak of the cycle they’re in at the moment,” the Scot said after seeing his side cut apart by a rampant Barca 3-1 at Wembley.

On Tuesday, Ferguson was in the stands at the Nou Camp for the ‘Clasico’ where he probably saw the Catalans’ cycle come to an end.

Ferguson, of course, was there for other reasons — to watch Real Madrid, United’s opponents in the Champions League next week, in action.

And from what he saw, he would be returning to Manchester with grave concerns as Real produced a mesmerizing display of counter-attacking football to stun Barca 3-1 in the Copa del Rey semi-final second-leg and reach the final.

It was the second cup reverse for Barca, whose trailblazing form in La Liga sees them 12 points clear of Atletico Madrid, in six days.

Last Wednesday, the Catalans were humbled 2-0 by AC Milan in their Champions League last-16 first-leg tie and against Real they looked a shadow of the side which has been so dominant in the league.

And now it seems as if La Liga is the only trophy they will end up winning.

World Player of the Year Lionel Messi was brilliantly kept quiet by Real’s defenders with the only clear sniff of goal for the Argentine coming in the opening couple of minutes when he screwed a shot just wide.

Real’s containment of Messi, who according to the Barca website was suffering from fever on Tuesday, has been dubbed by Spanish media as putting him ‘in the cage’ with four defenders marking him constantly.

In the first-leg at the Bernabeu, which ended 1-1, they tried it before Milan succeeded in it and on Tuesday, Real perfected it.

“Fans at the Nou Camp left the stadium before the end because they didn’t want to see a group which has become a shadow of what they were,” lamented Barcelona daily Sport on Wednesday.

“The game against Milan wasn’t an accident. Barca confirmed all their bad feelings against Madrid.”

It was Real coach Jose Mourinho’s finest moment at the Nou Camp since his Inter Milan side did exactly the same to knock out the Catalans in the semi-finals of the Champions League in 2010.

Now Inter’s city rivals Milan come to Barca’s gigantic arena on March 12 looking to do the same with the Catalans’ aura of invincibility of the last four years seemingly lost.

Barcelona midfielder Cesc Fabregas, the man who has been severely criticized during the last week, refuses to throw in the towel.

“This is a hard loss to accept but we have to pick ourselves up quickly,” the former Arsenal man told Spanish television channel Canal Plus after the game. “We need to learn from our mistakes and remember that we still have two titles to fight for.”

Real, meanwhile, signaled their statement of intent ahead of their second-leg against United next week although they have — what now seems the little matter of a — La Liga ‘Clasico’ against Barca at the weekend.

With Cristiano Ronaldo, who scored twice on Tuesday, in red-hot form, Ferguson would be hoping his former protégé doesn’t emulate his namesake on his return to Old Trafford.

A decade ago, Brazil legend Ronaldo scored a hat-trick for Real against United in their Champions League quarter-final at Old Trafford to dump Ferguson’s men out of the competition.

Real are seeking a 10th European crown, and Mourinho has made it clear that the Copa del Rey and the Champions League are his main priorities this season.