10 years of Marcelo have taught us that if he's really good going forward -and he is- it won't much matter how competent he is on defence. And carvajal is still an excellent player anyways, they can rotate
It's at left back that we probably need to move on from marcelo, whose body is breaking down
Not convinced Mendy is the answer. Good player to have in the rotation, but unless he improves significantly with the ball at his feet he's not going to be good enough to be a starter for us. Though i guess things might change if we can land Mbappé and won't have as much need to attack through the flanks