Ghana internationals Kevin-Prince Boateng and Sulley Muntari hit second-half goals as AC Milan stunned Barcelona 2-0, while Schalke shrugged off a form crisis with a 1-1 draw at Galatasaray in first-leg matches of the last 16 of the Champions League Wednesday.
Barcelona, seeking a fourth European title since 2006, were unable to break down seven-time champions Milan and were twice punished at the back to suffer their second defeat of the current competition.
Galatasaray, fielding winter signings Didier Drogba and Wesley Sneijder, meanwhile had to settle for a draw with Schalke, who now have the edge for the return in Gelsenkirchen.
Burak Yilmaz scored his seventh Champions League goal in seven games to put Galatasaray ahead in the 12th minute, but Jermaine Jones levelled for Schalke just before half-time.