That first half against West Ham the combination of Grealish/KDB was superb.The good thing is I do think he'll take up more central positions if he starts with Kev
Kev has been taking up a lot more positions out on the left in the games this season, obviously tactical, maybe he can preserve his legs a bit out there. The left sided player has been interchanging with Kev and drifting more central. That'll suit Jack down to the ground.
Grealish is a far better play when he comes inside, he is simply not a wide player.