I thought they played a 3-4-3 with Abidal, Mascherano and Busquets in defence? Keita in front. Either way, still impressive. There's previous in La Liga for central midfielders playing at centre back - mind - they like sticking a ball player there, especially if you're Barcelona and have very little to do defensively anyways.
Still hammered the team that finished fourth last time, 5-0, too. Which is ridiculous. Between them and Real Madrid hammering their opponents, and the two Manchester teams in England putting up big wins against supposedly top teams - then it could be a long hard slog for anyone not named Man Utd, Man City, Barcelona or Real Madrid.