AC Milan coach Max Allegri admits Barcelona's selection of David Villa took him by surprise.

Barca surprised by picking David Villa in the starting XI, but it proved a masterstroke.

"David Villa's position caused us a lot of problems. The passing was also so quick that we had to defend a little deeper. Despite it all, we had a great chance to get the away goal and even the equaliser. Against great champions, it's always difficult to qualify, even after the first leg.

"It's a shame we tended to give Barcelona opportunities by failing to clear the ball properly."