We saw plenty of rotation last season with full backs that weren't fit for purpose. It is guaranteed that we will see the same this season. There's probably approx 30 games each available for each for Walker and Danilo.
Nt really, who would you back yourself to get ahead of, Kyle Walker or Dani Carvajal? No brainer for me. Also he just wants out f Real as they've messed him around and the fans have turned on him. A fresh start is obviously what he needs. (I'd back him to beat Walker to our RB position tbh)
If he is covers for both positions here as well as being rotated then it's a good decision..Mendy(assuming we're getting him) is injury/card prone so he'll pick up game time at left back and be rotated on occasion with Walker, + sub appearances.
If he can beat out Walker, then fair play, but realistically, you have just paid £50m for him, he is going be your undisputed starter in most of your important games.
We'll see how it pans out, but I do not see him keeping Walker out of the side in a game that matters. Cracking player to have as back up though.