India coach Gautam Gambhir on Monday backed "incredibly tough men" Rohit Sharma and Virat Kohli to prove their critics wrong and find form in Australia.

Skipper Rohit and superstar batsman Kohli came under fire after India crashed to a humiliating 3-0 Test series home defeat to New Zealand.

Rohit scored 91 runs in three matches. Kohli made just 93.

Speaking just before India flew off to Australia for a blockbuster five-match Test series, Gambhir said he had "no concerns for Virat and Rohit".

"They are incredibly tough men," he said. "They've achieved a lot for Indian cricket and they will continue to achieve a lot in the future as well."

Gambhir hit out at Ricky Ponting after the former Australia captain questioned the longer-term form of the two senior batsmen.

"What does Ponting have to do with Indian cricket?" Gambhir said.

Gambhir said the Indian team as a whole were eager to prove themselves after the New Zealand defeat, only their second Test series whitewash at home.

"I feel there is a lot of hunger, especially after what has happened in the last series," he said.

Gambhir believes the biggest challenge in Australia will be the quicker pitches compared to India, where conditions are traditionally spin-friendly.

But Gambhir said his under-the-cosh side were ready to "fire from ball one" in a series that starts in Perth on November 22.

"We've been to Australia many times, so that experience will be crucial," said the coach, who has also faced some flak.

"If we play to our potential, we play our best cricket, we can beat anyone on any wicket."