AC Milan held Barcelona to a 0-0 draw in the first leg of the teams' Champions League quarter-final at the San Siro.
Milan should have been ahead just after the kick-off as Robinho found himself in space in the area, but he was unable to keep his close-range volley down.
Barca began to take control of the game, and Alexis Sanchez felt he should have been awarded a penalty as he went down following contact from goalkeeper Christian Abbiati, but the officials did not agree. Lionel Messi had the ball in the net soon afterwards, but the flag had already gone up for offside.
Barca continued to dominate the match, and Sanchez had a good opportunity as he burst clean through only to be denied by a last-ditch Luca Antonini tackle.
Chances in the second half were few and far between, but Abbiati had to make a smart save from Lionel Messi in the 88th minute and Antonini superbly blocked Cristian Tello's follow-up effort.
Bayern Munich look certain to progress to the semi-finals after securing a 2-0 away victory at Marseille.
Mario Gomez fired the visitors ahead before the break, with stand-in Marseille goalkeeper Elinton Andrade culpable, and Arjen Robben doubled their lead with a tidy finish in the second half.