With Xavi and Andres Iniesta playing behind you it's hard not to look impressive which makes it a difficult idea to argue against.On the evidence provided by the Champions League match against Ajax Amsterdam a few days ago however, it seems as if the reverse is true. It really does appear that Barcelona are not the all conquering force without Messi spearheading their attack. You do have to wonder though - how does a team laden with international stars, including most of Spain's world and European title winning team, struggle so much when missing just one key player. Messi is the best player in the world right now (and possibly of all time) but a team with Cesc Fabregas,The Flamboyant Neymar ,Pedro,Andres Iniesta, in attack should not be so listless.The shift in attitude and aptitude once the injured Messi was introduced is alarming. A one-legged player should not have such a rousing effect on a team that is considered one of the best that has ever played the game.It all leads to one question. What will Barca do if their little master picks up a serious injury? It is a scenario that the Catalans have fortunately not had to deal with yet but the omens are eerie.The Spanish titans looked aimless against Ajax.Every great team has a leader, a player that team mates turn to when the chips are down. The difference with Barcelona is the extent to which they rely upon Messi. They were unrecognisable from the team that has dominated the world for so long.They now have to find a solution to deal with Messi's absence in the future or else pray to the gods for some divine protection for the sublime Argentine.