I'd go with Pedro-Messi-Alexis against Atletico since Pedro and Alexis are on fire. Plus, Neymar was sick recently so he might not be at his best. And the extra defensive workrate can be helpful since it's a tough away game and all. And the competition will make Neymar even better.
Good game against by Pedrito and just like Flavia I really don't understand why he was subbed. Maybe Tata wanted to force something in the last minutes with adding an extra midfielder to our poor midfield and hoping for Messi & Neymar magic up top.
The thumbnail of that video was the moment when Caparros stepped in Pedro's way on purpose. Disgraceful act from their manager.