The drawbacks of the 4321 and playing with a 10 is showing up in the last two games.
He occupies the space the opposition DM naturally occupies, so if he's having a off day or the DM is having a class game, he will be easily marked out of the game.
In situations like these, he needs to drop deeper and pull his marker with him to create space for pedri or whomever is run into.
One of the reasons I like the PSG midfield so much is there positional rotations, with our midfield everyone bar pedri more or less keeps the position they start in.
Also this is by 433 is the best formation in football and we need to get back to it ASAP.