The thing with Mendy is that I believe his upside is so high. He's very intelligent in terms of movement, pressing, positioning, and picking out passes/crosses. His left foot is great. He's very athletic. He's a far better defender than he gets credit for. I honestly think that a fully fit Mendy with a few games under his belt could be as effective as Cancelo currently is albeit in his own way. Because of all of this, I'm willing to give him as long as the club gives him before writing him off.
But he's in an eternal cycle. Comes back, looks ok. Clearly not up to speed. Normally spends a small number of games focusing on defending. Then he starts to look good all of a sudden, like the old Mendy. Then he has a bad game and gets injured and that's the last we see of him for at least 2 months.
It's hard to ever be too optimistic with the guy. He could have an excellent month for us and then he falls over trying to head it back to the keeper, costing us the game and then he pulls his hamstring in the process of it all and that's it until next season.
But maybe it's finally time to have hope again. Until the next time we're having this conversation at least.