As you might have noticed, this lineup is exactly the same that defeated Real Madrid 5-0 in that historic and unforgettable November night. It's Barcelona's vintage XI.
But the season is long (Barcelona can play up to 65 matches) and Pep Guardiola will need to rotate his squad a lot to keep everyone fresh.
In defense, the likes of Andreu Fontás (CB), Adriano Correia (LB/RB) and Maxwell (LB) will be called upon on several occasions, with Javier Mascherano being a possibility for the center back role also (especially if Carles Puyol doesn't fully recover).
Given that Barcelona are a bit short on defense, youth players like Bartra and Muniesa might need to be called upon as well.
In midfield, Javier Mascherano will provide cover for Sergio Busquets, while Seydou Keita, Ibrahim Afellay, Thiago Alcantara and maybe even Cesc Fabregas will be more than enough cover for Xavi and Iniesta.
In attack, new signing Alexis Sanchez will slowly be integrated into the team, but he will surely have a role to play. He offers things that Villa and Pedro do not (pace, dribbling...) and will provide a new dimension to Barcelona's attack.
It's a long season and everyone will have a role to play. Barcelona have the best starting XI in the world, but that won't be enough. They need their squad players to be at their very best if they wish to continue their successful run.