It;ll be a close call but I think the result would be like 4-3 in the favor of Barca The advance of Carlos plus the shaky R.Junior on the left side would hand Messi a winning goal at the end
Barca would have the best player, far better midfield, better goalkeeper, better team chemistry/system and deeper bench. But other than that, it is pretty close.
Depends on how well Brazil can defend and counter because lets face it, they will have no more than 20-35% ball possession.
judging from how Ronaldo and Messi looked last night at the Ballon D'or awards... I'm gonna go for Barca!