Werner, on-loan from RB Leipzig, was publicly lambasted by Postecoglou after being hooked at halftime of Thursday's 1-1 draw at Europa League opponents Rangers.
It's been suggested Werner could now have his loan cut short in January.
But Postecoglou said, "Right now that is the furthest thing from my mind.
“I’m just not interested in what happens next. I’m interested in what happens now.
“Now is the time we have an opportunity. In these next five games between now and New Year we can set up our season.
"Last night (against Rangers) was a great point for us because it sets us up for Europe, so we know we’re going to make the knockout stages. Now we have four league games to get ourselves back up the ladder and make an impact.
“We’ve got a massive Carabao Cup quarter-final (against Manchester United) to get to a semi-final. I’m not interested in anything else beyond that.”
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