Ashes 2015: Michael Clarke defiant as Australia seek to salvage series

Nottingham: Australia captain Michael Clarke is determined to prove the doubters wrong and lead his country back into contention for the Ashes when the fourth Test against England begins on Thursday.

Clarke's poor form has contributed to Australia falling 2-1 behind in the five-match series but he bristles at suggestions that his Test career could be drawing to a close.

"I've had (criticism) throughout stages of my career, I've had it over the last couple of test matches so no different for me, my preparation has been exactly the same," the 34-year-old told a news conference at Trent Bridge on Wednesday.

"Like the team I look forward to coming out here and performing like we did at Lord's, try to put on a really good performance and I'd like to lead the way as captain."

Australia won the second test convincingly at Lord's but lost heavily in Cardiff and Edgbaston with Clarke rarely looking comfortable, despite a Test average of almost 50.

He says he is working overtime to try to regain his form.

"Getting out of bed to get better hasn't become tougher at all," Clarke said. "I think when that becomes too hard it's time to walk away, no doubt about it.

"If I didn't have the love I have for the game, didn't have the will to be the best I can possibly be and help this team have success, I wouldn't be sitting here today.

"So I've still got that love, desire and passion, I'm still trying to become better, that's why I'm here training today."

Clarke was made Australia's permanent captain in 2011 and steered his side to a 5-0 Ashes whitewash against England in the 2013-14 series on home soil.

He acknowledges, however, that this could be his last chance to win an away series in England.

"I think there's no doubt this is my last opportunity to win an Ashes series in England, for me personally and for a number of the guys," he said.

"There's no doubt every single one of these players in the changing room would love to win this test match, would love to go on and win at The Oval, win the Ashes in England.

"So it's not going to be from lack of desire, lack of preparation, lack of hard work; if you get beaten you get beaten but I'll guarantee we're going to have a red-hot crack at it that's for sure."