If Pep is smart, he will play something like this:
[formation=red,6]
Neuer
0-Benatia-0-Boateng-0-Lahm-0
Rafinha-0-0-0-0-0-Bernat
0-Schweinsteger-0-0-0-Alonso-0
0-0-0-Thiago-0-0-0
0-0-0-0-0-Götze-0
0-0-0-Müller/Lewandowski-0-0-0
0-0-0-0-0-0-0
[/formation]
Their best chance of getting a good result is to nullify Messi and the only player who can do that in their squad is Lahm. For me, if Lahm is anywhere else besides at LB/LCB, Bayern will be in trouble. They will learn that it's a lot harder to contain him then it was when he was a false 9. Especially with how well he cuts in from right to center, only Lahm can anticipate his movements and have the quickness to keep up with him.