On-loan from RB Leipzig, it's been suggested Werner could be sent back to Germany this month after his performance at Rangers earlier this season was branded "unacceptable" by Postecoglou.
But the Australian now says: "Yeah (I expect him to still be here after the January window). The last thing I want is to lose another player at the moment.
"The other night after Rodrigo went off, we had 11 first-team players out. We’re not letting anyone go at this point."
On his blast for Werner after Ibrox, he also stated: "It was feedback, it was what I obviously felt that day. I think he’s made an impact, even at the weekend when he came on, he’s got certain attributes that can hurt any team.
"You saw that at the weekend, he’s got a real turn of pace. We’ve needed that in games at times, particularly late in games.
"His attitude has never been a problem in terms of the way he trains, or the way he’s going about things. I felt that day, particularly with the situation we were in and him being a senior player, I thought he could have contributed more, but since then he’s made an impact as we’ve wanted to. There’s certainly never been any problems with his attitude."