Ricky Ponting has defiantly vowed to fight on as Australia's Test cricket captain despite facing the possibility of his third Ashes drubbing since taking over from Steve Waugh.

Once an almost immovable force in the Australian batting line-up, Ponting has scored just one century in his past 33 Test innings and registered single figures in six of his past 14 appearances.

"Retirement is the last thing on Ricky's mind. He's concentrating on the next three Ashes Tests and then the World Cup," said James Henderson, Ponting's agent.

"It's less than six months since Cricket Australia signed him on a two-year contract, which goes until July 2012, and there has been absolutely no consideration to him breaking this contract," the Daily Telegraph quoted Henderson, as adding.

Rumours began to surface on Tuesday afternoon in Adelaide that Ponting was under pressure to retain the captaincy, and his position in the side, if England wins one of the last three Tests to keep the Ashes.

A number of critics have taken potshots at Ponting in recent days over his captaincy and form, including close friend Shane Warne and batting legend Doug Walters.

Former opening batsman Michael Slater added to the speculation, suggesting: "Surely if we lose the Ashes, his future will be pretty bleak."

Despite pledging to continue until next year's World Cup at the very least, Ponting admits he is facing massive challenges over the remainder of the summer starting with the third Test in Perth.

"It's certainly a great challenge for me. Don't worry about winning the games ... I've got to make some runs, it's as simple as that," Ponting said after the Adelaide debacle.

However, if the selectors do decide to axe Ponting, Cricket Australia would be forced to pay out the balance of his $2.5 million contract.