WEMBLEY, England — Over 25 years Alex Ferguson has turned Manchester United into English football's most successful side, but an all-powerful Barcelona side is thwarting his quest for European domination.

A second Champions League final loss in three seasons on Saturday against Pep Guardiola's side allowed Barcelona to overtake United on the continent's role of honor with a fourth title.

While Guardiola has won the competition twice in three seasons coaching Barcelona, Ferguson has only won it twice in his United career.

"It's not easy (to beat them) but that's the challenge and you shouldn't be afraid of the challenge," Ferguson said. "The only thing we have shown is consistency in Europe."

To achieve that, though, Ferguson will have to find a way of closing down Lionel Messi, Andres Iniesta and Xavi Hernandez.

"In my time as a manager it is the best team we have faced," the 69-year-old Ferguson said. "I'll acknowledge that and accept that. It's not easy when you have been well beaten like that to think any other way. No one has given us a hiding like that."

And Ferguson's squad accept that Barcelona has set the benchmark for other players.

"We've got to work to get to that standard," defender Rio Ferdinand said. "They are a fantastic football team with great individuals, but more importantly, they are a great collective team

"We've got to aim to get to that and that's something for next season and we will come back fighting again next year."

But the manner in which United was outclassed and overwhelmed by Barcelona exposed the gulf in class between the champions of England and the champions of Spain.

The aggressive start made by the Red Devils on a Wembley pitch suggested they wouldn't capitulate like they did in the 2-0 loss in the 2009 final.

Even after Pedro Rodriguez put Barcelona in front, Wayne Rooney responded with an equalizer that turned out to be a rare moment of menace from the United striker.

Barca started the second half energetically, with Messi powering in his 53rd goal of the season in the opening ten minutes. The diminutive Argentina forward then created the second goal, with David Villa curling a shot into the top corner of the net.

"We gave it a better shot this time than last time," Ferdinand said. "A couple of the goals were preventable but you have to give credit where it's due."