Barcelona winning 4-2 against Slavia Prague is being celebrated, but it should be a wake-up call. You cannot concede two goals to a Czech side and expect to survive the knockouts. Lewandowski had to bail them out (again) after scoring a bizarre own goal. The defense is paper-thin. When they face a team with actual transition speed like Bayern or Arsenal, this high line is going to get exposed. They are 'entertaining,' not 'serious contenders