AC Milan could be in danger of missing both goalkeepers Dida and Zeljko Kalac when they clash with Premiership leaders Arsenal in the Champions League on Wednesday. Dida suffered a back injury while sitting on the bench during Milan's weekend 0-0 draw at Parma, and manager Carlo Ancelotti conceded that the problem was 'serious'. Moreover, the European champions announced that Kalac injured himself in training and is doubtful for the game. "Kalac dislocated the phalanx of his index finger on his right hand," read a statement on the club's official site. "His condition will be evaluated tomorrow to understand if he will be available for the London match against Arsenal." Ancelotti might be forced to select reserve goalkeeper Valerio Fiori for the decisive clash at Emirates Stadium.