Milan had chances to take a lead to Camp Nou next Tuesday, but Brazilian striker Robinho fired over the bar in the third minute, before Zlatan Ibrahimovic failed to beat Victor Valdes from point-blank range mid-way through the first half.
Barcelona forward Alexis Sánchez was convinced he had won a penalty after a smart free-kick routine resulted in Christian Abbiati clashing with the Chilean international.
However, the San Siro outfit kept Barcelona at bay in the second half to end the visitors’ nine-game winning streak, prompting Milan manager Allegri to heap praise on his players.
“I wish to congratulate my side on their performance,” said Allegri.
“We suffered more in the first half than the second, and Luca Antonini was brilliant marking Lionel Messi.
“We showed great commitment despite some difficult moments, and now we can think about the return – a draw or a win will see us through.
“We approached the game in two different phases, the defensive one and the attacking one.
“We played better football after the restart, but in the first half we created several clear chances and despite the regret at not taking them we gained confidence.
“The final result is fair, now we know we can achieve qualification in Barcelona. It’s very difficult to measure our chances for the return leg.”
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