He has 3 possible positions for me: either FB position or CM.
The FB berths are obviously where he should be: he has the engine to get up and down and he can carry the ball well enough. CM may suit too: he is competitive and could really add some punch in the middle with Doucoure. He'd have a fight on his hands dislodging Digne and Allan from LB and CM, but I can see him placing a lot of pressure on Coleman for the RB berth.
I dont see how he can be a CB. I really dont think he's careful enough on the ball to trust there with the ball at his feet and he cant seem to get his head on the ball (and that's taking into account Keane's gaffes too).
It's his second season here and he needs to secure a starting place somewhere soon if he isn't to just drift as some 'utility' player.