Stephan El Shaarawy is back and available for selection after missing the win against Parma at the weekend.
Mario Balotelli misses out, though, as he featured for Manchester season in the Champions League earlier in the season, so El Shaarawy could start centrally with Boateng and Niang out wide, though Pazzini is another option.
Milan still have a number of absentees, but their form has picked up recently and they seem to be dealing with their injuries rather well.
Both Xavi and David Villa remain doubtful after missing the win over Granada at the weekend.
Xavi is more likely to return, though, while Villa has spent some time in hospital with kidney stones and is thus very unlikely to feature.
Puyol and Iniesta were both given a rest at the weekend and should go back into the starting lineup at San Siro.
Adriano was replaced by Jordi Alba after only 38 minutes at the weekend, so the Spaniard could start here.
AC Milan and Barcelona faced off 4 times in last season's Champions League, meetings in the group stages as well as in the quarter-finals. They meet in the last 16 this time around, but it may well be the same old story.
Milan nearly spring a surprise by taking an early lead at Camp Nou in the first of those 4 meetings last term, but Barcelona learnt from their mistakes and went on to draw that match before winning 2 of the 3 other games.
Barcelona's form wobbled a little recently, with the Catalans winning just twice in a run of 6 games, but they have since won two on the trot and will be confident ahead of this trip. Milan have won 4 of their last 5 matches and are climbing Serie A with some speed, but this game will represent something of a different test for them. Without Mario Balotelli, Milan will be severely weakened and that could be crucial.
WhoScored.com provides you with unparalleled football statistics, as
well as detailed football previews and football rankings from competitions all over the
world. Our live, in-depth football statistics from the Premier League,
supplies unique and original insights for football fans, sports
betting punters, journalists, football managers and players. We also have football tables,
live scores, top performing players as calculated with our unique WhoScored.com
ratings, blogs, graphics, rankings and much more.