The German was taken off at half-time of Spurs’ Europa League 1-1 draw against Rangers.
Asked if it was a tactical move or if he was unhappy with Werner’s form, Postecoglou stated: “Yeah, yeah, he wasn’t playing anywhere near the level he should.”
He added: “Yeah absolutely. When you’ve got 18-year-olds it’s not acceptable to me. I said that to Timo.
“He’s a senior international, he’s a German international. In the moment we’re in right now, it’s not like we’ve got many options. I need everyone to at least be going out there trying to give the best of themselves. His performance in the first half wasn’t acceptable.”
On whether Werner took it well, he added: “Don’t really know. It’s not really of great concern. We need everybody including him to be contributing. because we don’t have the depth to leave people out if they’re performing poorly.
“We need them to play their part. Especially the senior guys. When I’m asking younger guys to do massive jobs. I expect a level of performance from some of the senior guys and today wasn’t that.”
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