Yeah, they were a great unit for the type of team we struggled with. That's football. Barcelona at that time reached a passing, dribbling, and technical level that made them impossible to be pressed or dominated. So you'd need the best defensive side around to have a chance vs them. A team to absorb pressure like crazy, dominate the box for any crosses, put as many bodies behind the ball as possible, and be clinical on the break. Dirty tactical fouls, time wasting whenever possible, any sneaky tactic is obligatory.
Carvalho, John Terry, Ashley Cole, Essien, Makelele. This is one of the best collections of defenders I've ever seen in the same team.