Ange Postecoglou has urged Tottenham to embrace the challenge of trying to end their long trophy drought and said he is happy to be regarded as a failure if he does not win anything this season.

The Australian was in a defiant mood before visiting Coventry in the third round of the Carabao Cup on Wednesday night and is determined to maintain his record of lifting silverware in his second year in a job.

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Spurs’ most recent trophy was the League Cup in 2008 and Postecoglou, who has faced criticism since losing to Arsenal last Sunday, wants the club to adopt a fearless mindset in pursuit of glory.

“It’s why I came here,” the former Celtic manager said. “I came here to try to win things. I think that should be our measure and if we fall short of that then we’ve fallen short and we need to be better. I don’t think there’s anything wrong with embracing that.

“It’s just the way I’m wired, I think it’s the way forward and you need to embrace that if you want to become a successful club and not shy away from it. If I said: ‘This is going to take three or four years,’ then yeah it would relieve pressure. But I don’t want to wait three or four years. This year’s an opportunity.”

Postecoglou, who has made an inconsistent start to his second season, insisted he had no problem with being judged a failure if Spurs end up empty-handed again.

“I failed last year in my head because that’s how I’m geared,” he said. “I think I’ve made it pretty clear what my expectations are. But that doesn’t mean that I stop. That just fuels the fire of ‘why didn’t I do it?’ That gets me going for this year and this year it’s about progress. That’s been my whole career.

“Have I ever downplayed anything since I’ve been here? So I’m willing to be measured against that – that means that I’m fair game. I’m happy to be judged against that standard because that’s my standard, that’s what I’ve done in the past and I don’t want to dilute that. I have no problems with people using that as a yardstick.”

A potential issue for Spurs, whose heavily rotated side lost in the Carabao Cup second round to Fulham last season, is that it is 11 years since anyone other than Chelsea, Liverpool, Manchester City or Manchester United won the competition. But Postecoglou remains undaunted.

“I don’t think there’s anything limiting this club having success,” he said. “I really don’t believe that. That’s why I’m here. But that doesn’t mean we’re ready for it now. It just means it’s what we should be striving for.”

Spurs have lacked a clinical touch this season but Postecoglou defended Brennan Johnson after the winger deleted his Instagram after receiving abusive messages on the back of his performance against Arsenal.

“I hate how we’ve just normalised all that stuff,” Postecoglou said. “You’re talking about a young guy who is probably lacking a bit of confidence at the moment. Things haven’t gone his way.

“But he comes here every day, he’s working his backside off, he’s doing everything right, he’s trying so hard to become the player he wants to be. It’s hurting him a lot. It’s not like he’s out on the town and he doesn’t care and he rolls up late. So what’s his crime? His crime is he isn’t performing at the level that people expect of him.

“As a professional footballer you’ve got to expect that you’re going to get criticism. He’s still a young player and I think there is so much more of Brennan that we’re going to bring out in him.”