Barcelona overturned a first-leg loss to advance to the quarterfinals of the Champions League, earning a 4-0 defeat of AC Milan at Camp Nou on Tuesday to go through with a 4-2 aggregate score.

The Catalans scored twice on either side of halftime to go through to the next round as a first-half brace from Lionel Messi was supplemented by goals from David Villa and Jordi Alba after the restart.

It took Barcelona just five minutes to get off the mark as Messi curled a superb left-footed shot into the upper corner from outside the box, rooting Christian Abbiati to the spot.

The Catalans nearly leveled the aggregate score eight minutes later when Andres Iniesta's shot from distance was pushed onto the crossbar by Abbiati. Messi followed up the shot but sent his header wide of goal.

The visitors struck woodwork themselves in the 38th minute when M'baye Niang split the Barcelona defense to go one-on-one with Victor Valdes, but the Ghanaian striker saw his effort trickle back into play off the base of the post.

It proved to be costly miss for Milan as Barcelona's Argentine magician scored a minute later. A giveaway from the Milan defense was picked up by Iniesta, who played a brilliant ball into Messi's feet. The 25-year-old drifted inside and fired a low shot past Abbiati to send the two sides into the halftime break even on aggregate.

Barcelona continued to maintain the majority of possession into the second half and made the most of it when Villa produced the third goal of the match. A failed interception from Kevin Constant allowed Villa to get into scoring position on the right side of the penalty area, and the Barcelona striker made no mistake with the finish, slotting a shot past Abbiati at the far post.

AC Milan pushed in search of an away goal that would have seen the Serie A through to the quarterfinals, but Barcelona exploited the Italians in stoppage time when Alba latched on to a switch from Alexis Sanchez and chipped a shot over the on-rushing Abbiati to secure the insurance goal.

Galatasaray 3, Schalke 2

Gelsenkirchen, Germany - Galatasaray clinched a spot in the quarterfinals of the Champions League on Tuesday with a 3-2 win over Schalke at the Veltins Arena.

Following a 1-1 opening leg in Turkey, Schalke was well-positioned to advance when Roman Neustadter put the German side in front after 17 minutes.

But Galatasaray answered with two goals before halftime as Hamit Altintop's superb dipping strike worked from a short set-piece in the 37th minute saw the visitors go level before Burak Yilmaz latched on to a looping ball over the top to fire the Turkish side in front five minutes later.

Michel Bastos bagged Schalke's second goal of the night just after the hour mark to give the Bundesliga club a fighting chance down the stretch, but Galatasaray ensured its place in the next round when second-half substitute Umut Bulut beat the offside trap and converted a late chance from close range.