MILAN - A hotly-protested goal by Kevin-Prince Boateng set AC Milan on their way to a shock 2-0 win over Champions League favourites Barcelona in their last-16 first-leg tie on Wednesday.

AC Milan's Kevin-Prince Boateng reacts at the end of the team's Champions League soccer match against Barcelona at the San Siro stadium in Milan February 20, 2013. [Photo/Agencies]

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.    

"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 added.

The return leg is on March 12.

Barcelona's Lionel Messi (L) and Xavi Hernandez react following AC Milan's second goal during their Champions League soccer match at the San Siro stadium in Milan February 20, 2013.[Photo/Agencies]

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