If you look at Bayern last season, they really didn't have a lot of options in the central midfield either. It was mostly between Thiago, Vidal and Alonso. These are good midfielders, but not like what Pep had at Barca. Thiago isn't as good as Xavi or Iniesta, Vidal is more like Dihno and not on the level passing wise and Alonso wasn't exactly quick and was getting on in age as well. He also used Lahm in the midfield. Pep knew his midfield wasn't quite at that level of the Barca players, but found other ways to play out from the back. He'd tuck in the fullbacks to flood the midfield and make the center backs play out to the wingers directly or over the top when possible. Pep's a smart guy and will know how to compensate.