BARCELONA, Spain (AP) -- Players hugged each other on the field as 90,000-plus fans sang and waved flags in the Catalan colors of red and gold.
Weeks of mediocre play had been washed away. With a dominant, historic performance, Barcelona restored its reputation as the world's best soccer team, the one with the flashy passing game others keep trying to duplicate.
Barcelona's 4-0 mauling of AC Milan on Tuesday night not only advanced the Blaugrana to the Champions League quarterfinals and kept alive their bid for a fourth title in eight seasons, it helped regain the confidence that dissipated with the illness of coach Tito Vilanova, a first-leg defeat in Milan last month and consecutive losses to Spanish rival Real Madrid.
"Beyond the result and moving on to the next round, we have returned to our origins, and that is what we must feel most satisfied about," Barcelona defender Javier Mascherano said Wednesday. "The fact that we strung together some bad games undermined our confidence and our way of playing. On Tuesday, our fans went home knowing that they had seen their team again."
While Barcelona is 23-2-2 in the Spanish league and has a 13-point lead with 11 games left, it was eliminated in the Copa del Rey by Real Madrid with a 3-1 defeat at Camp Nou on Feb. 26. Then it lost 2-1 at Los Blancos in a league match four days later. Combine the 2-0 first-leg loss at Milan on Feb. 20 and the absence of Vilanova since mid-January while he was treated in New York for a saliva gland tumor, and Barcelona fans were beginning to doubt.
Even Barcelona defender Dani Alves had said Monday that Lionel Messi -- at age 25 already a four-time FIFA Player of the Year -- appeared "down" to him. Alves said the team had lost the "hunger" required to carry out its high-intensity pressing on defense.
Not exactly what the players and their fans had become accustomed to under Pep Guardiola, who led the team to 14 of a possible 19 titles from 2008 under stepping down last summer.
No team had ever advanced in the Champions League after losing the first leg 2-0 on the road. But Messi scored in the fifth and 40th minutes, David Villa and Jordi Alba added second-half goals, and Barcelona reached the quarterfinals for the sixth straight season.
"We came out flying from the very beginning, We looked for our first goal from the starting whistle. We believed we could turn the tie around, and with that attitude a lot can be accomplished," Villa said. "We're very pleased for the fans. They have always believed in us and they haven't criticized us along the way."
In a little less than two hours, Barcelona's self-esteem has been restored.
"We will remember this for years," Barcelona director of football Andoni Zubizarreta said.
Milan, an eight-time winner of Europe's top club competition, was overwhelmed.
"Barcelona is the best team in the world," Milan coach Massimiliano Allegri said after his team's first four-goal loss since 2010. "Barcelona's pressure in the first half was lethal. They played a beautiful and fast-paced brand of football. They deserved to go through after playing the perfect game. Just because they had lost two or three matches doesn't mean they had lost their potential."
Barcelona assistant coach Jordi Roura, running the team while Vilanova is under treatment at Memorial Sloan-Kettering Cancer Center, made two changes from the lineup that lost in Milan. Roura inserted Mascherano and Villa for 34-year-old captain Carles Puyol and Cesc Fabregas.
Mascherano's interception of a pass started the play that led to Villa's goal in the 55th minute, which gave Barcelona a 3-2 aggregate lead.
"These days have been difficult," Roura said. "My players received undeserved criticism, but they went out and got a good result and proved that they are made of something special. One is always surprised by these players, who having won so much, still take a loss so much to heart."
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