he should have simply do this:
Ait Nouri, Guehi, Dias, Nunes defence
Cherki, Rodri, Bernardo midfield, and up top Doku, Haaland, Semenyo
to bring in Savinho on RW, just to push Semenyo to middle where he looked uncomfortable and doesnt really make things happen in build up, take NOR out of midfield to put back to LB for no reason, leave Nunes out these are all odd things to come up in a CL 1st leg vs Real madrid.
if we play Sporting or Atalanta, yes you can make these changes and get away with it maybe.
Pep was punished so hard for his tactical mistakes, its almost "funny". there are games where your tactical mistakes aint result in a big loss or you can blame bad luck more or the ref etc. but not in this game.
this would have been 4-0 if Donnarumma doesnt save the pen. and he had another big save from Brahim shot I think in early 2nd half. their keeper also had a top save vs OReilly central shot. take away the great saves and its 5-1 realistically.