Ghanaians Kevin-Prince Boateng and Sulley Muntari both scored in a lively second half as AC Milan inflicted a shock 2-0 defeat on Barcelona in their Champions League last 16, first leg, at the San Siro here Wednesday.
Milan, crowned European champions seven times, had failed to beat the Catalan giants in the competition since a 2-0 win at the Camp Nou in 2000 and had exited the competition last season and in 2006 after defeats at the hands of Barcelona.
But, after a promising first-half display was taken up a level in the second period, fans of the Rossoneri were given reason to believe that their team can advance to the quarter-finals.
In a tight first half, Barcelona toyed with the hosts' defence without really putting 'keeper Christian Abbiati in danger.
Milan sought to get men behind the ball but were still left rueing several missed chances.
On 16 minutes, an unmarked Giampaolo Pazzini failed to convert Boateng's first-time effort from Stephan El Shaarawy's corner at the far post.
French defender Phillipe Mexes then did well at the other end with a saving block at the near post from a dangerous Pedro Rodriguez cross.
El Shaarawy then missed a great chance for the opener, prompting a torrent of abuse from angy home fans, when he ran on to Boateng's ball on the left only to fire tamely towards Valdes.
From the striker's ensuing corner, Boateng produced a great first-time effort with the outside of his foot that went inches past Valdes' far post as Pazzini stood rooted.
El Shaarawy was then unlucky not to reach Boateng's floated ball in from the right on 36 minutes after Muntari had done well to win the ball in midfield.
No changes were made at half-time, but the game itself went on to change dramatically.
On 53 minutes tempers frayed when Sergio Busquets brought down Pazzini in midfield, earning the Spaniard a yellow card.
Moments later the San Siro erupted when Boateng pounced to give Milan the opener.
A Riccardo Montolivo free-kick from 30 metres bounced fortuitously off the hand of Cristian Zapata for Boateng, who beat Valdes with a superb strike from the edge of the area.
Barca protested but Scottish referee Craig Thomson responded by showing a yellow card to Gerard Pique.
Barcelona were showing little of the cohesion and possession football they had displayed in the first half while Milan, growing in confidence, were getting more bullish.
On 63 minutes, Barcelona replaced Cesc Fabregas with Alexis Sanchez but the change had little impact as Milan continued to frustrate the Catalans.
The visitors had barely threatened the home goal until an Andres Iniesta strike from the edge of the area shaved the far post, and they then fell further behind in the 81st minute.
Muntari, unmarked on the left of the area, finished off some neat build-up play by El Shaarawy and M'Baye Niang to beat Valdes with a superb angled strike.
Barca rallied in the dying minutes and Puyol was unlucky with a bullet header when he rose to meet a corner from the left, but they were unable to get what would have been a precious away goal.