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 on Wednesday.
A hotly-protested goal by Boateng set AC Milan on their way to the victory over Champions League favourites Barca.
Barcelona, who eliminated Milan last season, surrounded the referee claiming Cristian Zapata had handled the ball before it landed at the feet of Boateng who smacked it into the net in the 57th minute.
Barca, who had dominated possession in their familiar style, lost their grip on the game after the incident and were sunk by a second goal from Boateng's fellow Ghanaian Sulley Muntari.
"There is no excuse from the pitch or the referee. We'll look forward to the return leg now and try to win"
Barca defender Gerard Pique
"It's very bad (for the return leg)," Barcelona defender Gerard Pique said in an interview with Spanish television broadcaster Canal Plus.
"The first half wasn't bad and we controlled the game but when they scored the first goal we lost that control and they were able to take their second chance.
"We have to improve and learn and try to turn things around at the Camp Nou.
"There is no excuse from the pitch or the referee. We'll look forward to the return leg now and try to win," he said.
The return leg is on March 12.
Even Barcelona top scorer Lionel Messi, who has netted in the last 14 La Liga matches, struggled to make his mark with a muted performance.
Barca rallied in the dying minutes and Carles 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.
Milan were clearly delighted with the victory after failing to win in their previous seven meetings with Barcelona and starting as rank outsiders with a team mostly assembled during the course of the season.
Didier Drogba impressed on his Champions League debut for Galatasaray but the Turkish side were held to a 1-1 draw by Schalke 04 after an entertaining last 16 first leg.
The Ivory Coast striker, last year's Champions League hero for Chelsea who moved to the Istanbul club last month after a spell in China, linked up well with Burak Yilmaz in attack.
Yilmaz scored his seventh goal in seven Champions League matches, putting Galatasaray ahead in the 12th minute when he picked up a pass from Selcuk Inan and flicked the ball around a defender to power in a shot past keeper Timo Hildebrand.
| Jermaine Jones scored a well-worked equaliser which puts Schalke in a strong position in the tie [AP]
Schalke equalised in the closing seconds of a pulsating first half.
The visitors broke quickly, Jefferson Farfan passing across the goal to Jermaine Jones who side-footed past Fernando Muslera, leaving the German side well placed ahead of the second leg.
Dutch playmaker Wesley Sneijder, another big-name acquisition by ambitious Galatasaray, was substituted after the first half.
Schalke, in poor form in the Bundesliga, began strongly with Jones cutting in from the left and firing in a shot, forcing a save from Muslera in the first minute.
The visitors had a chance to equalise soon after Yilmaz's opener, but Klaas-Jan Huntelaar failed to steer the ball in at the far post.
Yilmaz had another chance to score in the 38th minute when Drogba put him through on goal but Hildebrand blocked his shot.
The match continued to alternate attacks in the second half and Farfan had a chance to put the visitors ahead in the 55th minute but his effort was blocked by Sabri Sarioglu.
In the final stages, Galatasaray pressed hard for an equaliser but Schalke hung on for a draw.