Every new captain has to deal with the ghosts of his predecessor, but Michael Clarke will have the real-life version in the dressing room. The leadership could be Clarke's for years or it might last the length of the fifth Test, depending on what happens when Ricky Ponting returns from his broken finger.

The temporary nature of Clarke's promotion was highlighted by Ponting at an official function on Saturday when he responded to a speech from Julia Gillard, Australia's prime minister, instead of Clarke. Ponting, who is hanging around to have his injury treated, has also been working as an extra coach by passing on tips to the batsmen in the nets. Yet he has told Clarke to make his own decisions.

"Ricky's made that very clear," Clarke, Australia's 43rd Test captain, said. "Once I take that field they [the decisions] will come from me."

The uncertainty over his tenure, and the troubled state of the team, makes it a difficult assignment for Clarke. A photograph of Clarke and Gillard in Sydney's Sun-Herald today had a caption that said: "One of these people has the toughest job in Australia, the other is the prime minister."

Clarke starts the year with more responsibility, two debutants, concerns over his batting form and a mixed reaction to his appointment. The Ashes have already been retained by England and the hosts' best-case scenario is earning a win that will draw the series. Australia's past four captains have been promoted with the team on top of the world while Clarke's men are taking water at No. 4.

The environment limits what Clarke can do, but he has already made a notable alteration. Usman Khawaja and Michael Beer will receive their baggy greens from past Australian players instead of the captain, which has been Ponting's preferred system. Clarke named the team the day before the game so the debutants could get used to the idea they were playing. Ponting had kept Beer waiting until just before the toss in Perth to tell him of his fate.

Clarke received his baggy green from Shane Warne in Bangalore in 2004. While he was too excited to hear anything Warne said back then, he has since listened closely to all his advice and watched the way he played and led.

"Warney was a very aggressive captain, I don't think I'm that aggressive, but I've learned from him on the field," Clarke said. "He's a friend, first and foremost, but especially when I was a young player, he's been a mentor as well.

"I just hope that come tomorrow, I back myself, back my judgment, back my instinct. That's what people who have helped me have told me throughout my career, as a leader and vice-captain. Hopefully I continue to do that."

He intends to be true to himself whatever happens. "Some people are going to like that, some people aren't," he said. "I'm not that concerned about it. What I'm concerned about is me getting out there and scoring some runs for Australia and helping this team win."

Clarke was relaxed, polite and cautious when he spoke on the eve of the game. He said his first days in charge had been fun, but the serious business of stopping England was about to begin. "There's been a lot of talking about what's happened in the past month and not achieving our goals that we set ourselves in India," he said. "It's a new focus, a new year."

The results have hurt Clarke and the campaign already feels like a defeat, even though it's 2-1 to England. "I've been involved in four Ashes series and lost three of them," he said. "I remember fondly in 2007 when we won the series 5-0. We still have so much to get out of this last Test match. We can't regain the Ashes but we can level the series."

In a quirk of the modern game, Clarke will be captaining his maiden first-class match. When he has played for New South Wales, Clarke has been ordered around by Simon Katich, Brad Haddin or Stuart Clark, while Ponting has been the boss for all off his deputy's 68 Tests. Clarke wants Ponting back and fit as soon as possible, playing until "in 10 years when he retires".

Clarke said he is "very comfortable" with Ponting being in the dressing room. "Ricky being around throughout this Test is a great thing for all the players, but especially for me to have this chance to be captain," he said. "I can run things by him and I think it's pretty important for the team to have him around." Even though Clarke is the leader, it's clear it's not his team yet.