problem has anything to do with any individual player.
"The team works when everyone does their job and doesn't work when we don't all show up. We just have to keep improving."
Barca lead Champions League Group H with seven points from three games. Milan, who held the Catalan side to a 1-1 draw at the San Siro last month, are second on five points.
Celtic have three points and Ajax one ahead of their clash in Amsterdam on Wednesday.