With the absence of Lallana I definitely expected him to start at least the odd game in the middle, maybe Klopp just doesn't think he's quite ready just yet.
He's so young that unless we need him, it's arguably better to shelter him from the pressure of the first team and give him the odd game here and there.
We actually have quite a few midfielders to rotate and give minutes too when you think about it: Coutinho, Lallana, Hendo, Can, Gini, Milner, Ox, Grjuic, Woodburn
That put's Woodburn somewhere around 8th/9th in the pecking order.
Looking at that list actually, we do have a tonne of depth in midfield. There's 2 top players & 2-3 highly promising youngsters (plus more in our youth setup that are just one tier down). The problem is that the 4 names in the middle are very... 'OK'.