BARCELONA: Hailed as perhaps football's greatest team ever, Barcelona faced a challenge no club had overcome: advancing in the Champions League after a 2-0 first-leg loss on the road.  

Lionel Messi & Co. came through in spectacular fashion with another record-setting night.

Messi started the revival with a pair of first-half goals as Barcelona overwhelmed AC Milan 4-0 Tuesday to reach its sixth straight Champions League quarterfinal with a 4-2 aggregate win.

''It had been a long time since we had pulled off a historic comeback,'' Barcelona midfielder Xavi Hernandez said. ''We pressed them very well and played an exceptional match.''

Messi scored in the fifth and 40th minutes, and David Villa and Jordi Alba added second-half goals.

''We went out gunning from the start, and scoring early helped us,'' Villa said. ''We have believed in the comeback ever since we lost in Milan, and belief combined with hard work is how you achieve things.''

Before a screaming crowd of 94,944 at Camp Nou, Europe's largest stadium, Messi scored his first goal to goalkeeper Christian Abbiati's right with curling left-footed shot into the upper corner from 17 yards between two defenders. The goal moved Messi past Ruud van Nistelrooy into sole possession of second on the Champions League career list with 57, trailing only Raul Gonzalez's 71.

Messi then scored his second goal to Abbiati's left with a low 19-yard shot after Andres Iniesta stole the ball from Massimo Ambrosini.

''For anyone who doubted Messi, today Messi gave a lesson on how to play football,'' said Barcelona assistant coach Jordi Roura, in charge while coach Tito Vilanova undergoes treatment in New York for a saliva gland tumor. ''He is extraordinary, and surrounded by great players, he is capable of doing what he does.''

Villa put Barcelona ahead in the series in the 55th minute with a 14-yard shot after Cristian Zapata's weak clearance was intercepted by Javier Mascherano, and Kevin Constant missed a sliding tackle on Xavi's through pass to the forward.

Alba sealed the win in the second minute of stoppage time when he raced the length of the field on a counterattack after Messi stole the ball and passed to Alexis Sanchez on the break.

''Milan only needed a goal, but we knew how to handle the game very well,'' Alba said. ''This is a very important win for us. A lot was at stake.''

AC Milan, a seven-time champion, won the first leg at San Siro on Feb 20 and nearly got a valuable away goal in the 38th minute, but 18-year-old forward M'baye Niang hit a post with an open shot after a sloppy headed backpass by Mascherano. If Niang had leveled the game at 1-1, Barcelona would have needed at least three more goals at that point to advance because away goals are a tiebreaker.

''Barcelona is still the best team in the world. Moving on was a true feat,'' Milan coach Massimiliano Allegri said. ''The first leg didn't change these two teams, and whoever thought so was wrong. We played worse than in the first leg, but that is to Barcelona's credit.''

Messi, the four-time FIFA Player of the Year, got his 18th multigoal game of the season and increased his season goals total to 53.

Led by the 25-year-old Messi, Barcelona is seeking its fourth Champions League title in eight years and is closing in on its sixth Spanish league championship in nine seasons.

Milan lost by four goals for the first time since a 4-0 Champions League defeat at Manchester United in March 2010.

In the night's other match, Galatasaray won 3-2 at Schalke to advance on 4-3 aggregate and reach the quarterfinals for the first time since 2001.

After Roman Neustaedter put Schalke ahead in the 17th minute, Galatasaray took a 2-1 lead when Hamit Altintop scored against his former team in the 37th and Burak Yilmaz got a goal in the 42nd. Michel Bastos scored for the hosts in the 63rd, leaving the Turkish team ahead on away goals, and Umut Bulut ended any doubt when he scored for Galatasaray in the fifth minute of stoppage time.

Real Madrid, Juventus, Borussia Dortmund and Paris Saint-Germain also are in Friday's quarterfinal draw. In the final second-round matches Wednesday, Arsenal tries to overturn a 3-1 deficit at Bayern Munich and Porto goes to Malaga with a 1-0 lead.

If Arsenal is eliminated, England won't have a team in the last eight for the first time since the 1995-96 season.