But, bullish Postecoglou was unshaken in a Sky Sports interview as he vowed to win something at Spurs this season despite falling to Arsenal.
In a live interview, Postecoglou was asked: "You said at the start of the season, the first campaign was really about setting principles and getting your message across, the second campaign you normally win.
"Are you seeing enough in this side that this season you do think they will be a side that can win?
"I'm talking silverware, competing right at the top..."
The manager - who won a treble at Celtic in his second season - bit back at the questioning as he was interrupted quickly after beginning to respond.
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In a sharp reply, Postecoglou said: "Yeah, absolutely. If I can answer the question...or are you going to keep asking it?"
He then continued: "Absolutely. I'll correct what I said, I don't usually win things, I always win things in my second year. Nothing has changed."
Further pressed on the matter of whether he believes his current crop of Spurs players can win a trophy this season, Postecoglou added: "Well, I just sort of said it now. I don't say things I don't believe in."
Meanwhile, Postecoglou will be back in Glasgow this year when Spurs take on Rangers in the Europa League.
The former Celtic boss will head to Ibrox on December 12 in the revamped league phase of the competition.
On the trip back to Scotland, and Ibrox, Postecoglou previously joked: "Exciting. It's good to be a part of. Some good games. I am sure I will get a warm reception at Ibrox and they'll look forward to seeing me."