Australian captain Michael Clarke has adopted a siege mentality ahead of the Ashes opener in Brisbane.

After nine Tests without a win and six weeks caught up in a civil war threatening to split Australian cricket, Michael Clarke has decided upon being the new Captain Grumpy.

It was Allan Border who originally took on that persona, leading Australia out of some dark times in the 1980s with his tough love approach.

More than 20 years later and in the midst of another rocky chapter for the Test team, Clarke opted for the same siege mentality ahead of Thursday’s Ashes opener in Brisbane.

Clarke was straight to the point during a tense 12-minute press conference on Wednesday at the Gabba.

Australia are fighting to avoid a fourth-straight Ashes series defeat for the first time since the 1800s, and the most obvious conclusion to draw would be that Clarke is feeling the heat.

However, it may also be a deliberate ploy to take the attention away from his side.

The lead-up to this Ashes series has been dominated by Australia talking up their chances, and former greats slinging mud.

Clarke, who has been under further scrutiny himself after criticism by former captain Ricky Ponting in his recent, biography, clearly decided it was time to shut up shop.

Asked, was he bothered by the external criticism, Clarke said:

“Not one bit.”

And he also refused to be drawn on whether this was a different Australian side to the one that went down 3-0 to England in the winter.

“I don’t want to compare. Two completely different series. Different conditions. What is important is today; and tomorrow is important as well,” he said.

“The belief is there and hopefully we’ll show that over the next five Test matches.”

Combative opener David Warner said on Tuesday that England would fear Australia at the Gabba, a venue they haven’t lost at since 1988.

England skipper Alastair Cook didn’t miss a beat in his response.

“We certainly don’t fear anyone, that’s quite clear to see the way we go about our business,” he said.

“We are a very competitive side and there’s no reason to fear any side out there.”

The Gabba Test is crucial to Australia.

Losing at their Brisbane fortress would be extremely difficult to come back from, but a win could set up the series, with a flat Adelaide deck and a bouncy WACA to come.

Clarke refused to confirm his XI for Thursday, with spinner Nathan Lyon and seam bowling allrounder James Faulkner competing for the one spot.

Lyon is favoured given the strong record of spinners at the Gabba, but Clarke said selection debates were still going on – Faulkner a stand-out for Australia in their last Test at The Oval.

Shane Watson’s fitness is pivotal for Australia in the first Test.

Clarke says Watson should be at 100 per cent with the bat, but only half capacity with the ball.

For Australia, it’s not about Watson getting through, it’s about him making a difference.

In the last Test he played at The Oval in August, Watson scored the first hundred by an Australian No.3 since 2011.