Deprived of the services of injured striker Samuel Eto'o, Barcelona coach Frank Rijkaard opted to play Ronaldinho in a central role, flanked by Lionel Messi and Ludovic Giuly up front.

Recalled Mexican defender Rafael Marquez was employed in the midfield holding role, but lost possession several times in the opening stages as Zaragoza's pressured the Catalans' three man defensive line formed by captain Carles Puyol, Frenchman Lilian Thuram and Oleguer.

With just two minutes on the clock, Andres D'Alessandro tested Victor Valdes with a rasping angled drive, after being set up by Sergio Garcia.

Barcelona were simply not in the game early on and Uruguayan full-back Carlos Diogo was taking advantage of the extra space to get forward.

On one of his charging forward runs, the South American forced Valdes into a brilliant one handed save.

At the other end, Messi tested Cesar for the first time after a good combination between Giuly and Andres Iniesta.

But Zaragoza were dominating possession and D'Alessandro fired a free-kick just over the bar from 25 yards.

The Argentinian tried his luck again from another free-kick on 27 minutes, but Valdes got down well to make a comfortable save.

Sergio Garcia then beat Puyol and sent an angled shot just past the post as Zaragoza edged ever closer to an opening goal.

Diogo was also still causing problems for Barcelona and set up Garcia on 37 minutes, but the forward could not keep his shot down and Barcelona breathed a sigh of relief once more.

As half-time approached, Ronaldinho had his first shot, but was well off target and picked up a booking a minute later following a poorly timed challenge on Pablo Aimar.

Despite their ineffective play, the Catalans went in on level terms at the break.

Rijkaard changed things around at the interval and Italian full-back Gianluca Zambrotta came on for Marquez.

There was an immediate improvement from the Spanish champions and after Diego Milito tested Valdes after 48 minutes, Barcelona enjoyed their best spell of the game.

Ronaldinho set up Giuly and the French winger was denied at the second attempt by Cesar.

The former Real Madrid goalkeeper was alert again on 52 minutes, coming out quickly to intercept Zambrotta's cross, which had been intended for Ronaldinho.

Deco then saw his shot deflected behind for a corner as Barcelona began to pressure.

But a minute later, they were behind.

D'Alessandro showed some tricky footwork on the byline and crossed brilliantly for Milito, who got the slightest of touches to nick the ball past Valdes from an acute angle to put Zaragoza in front after 56 minutes.

After the goal, Barcelona were still unable to find their rhythm and Rijkaard brought on Eidur Gudjohnsen for the disappointing Giuly after 65 minutes.

The Icelandic forward gave Barcelona more balance up front and should have equalised after 73 minutes.

Another substitute, Dutch defender Giovanni van Bronckhorst, crossed from the left and the ball fell to Messi, whose left foot shot was cleared off the line.

The rebound then fell to Gudjohnsen five yards out but the former Chelsea forward dragged his shot just wide.

Despite their need for a goal, Barcelona created little in the final stages and Zaragoza held in for an important victory.