Cricket fans have a chance to bid on Warne's Test cap until Friday night, with all proceeds to be donated to the Australian Red Cross to help those affected by fires around the country.

The item would rank among the most valuable mementos from the decorated career of Australia's all-time leading wicket-taker.

Sir Donald Bradman's baggy green sold for approximately $420,000 in 2003.

Bidding for Warne's cap, which will come with an autographed certificate of authenticity, hit $200,000 a tick over an hour after opening.

Warne, who joins Ash Barty, Daniel Ricciardo and many others on a long list of high-profile members of Australia's sporting community to announce fund-raising measures, suggested it was the least he could do.

"The horrific bushfires in Australia have left us all in disbelief," Warne said.

"The impact these devastating fires are having on so many people is unthinkable and has touched us all. Lives have been lost, homes have been destroyed and over 500 million animals have died.

"Some of the images we're seeing are absolutely horrific."

Collingwood star Dayne Beams also announced on Monday he was putting his 2010 AFL premiership medal up for auction to raise funds for bushfire victims.

Barty is donating all her prize money from this year's Brisbane International to help bushfire victims, while Ricciardo is auctioning a race suit from the Australian Grand Prix.

A stack of cricketers are donating sums of money based on how many sixes they hit or wickets they claim in this summer's Big Bash League.

Australia's Test attack has pledged $1,000 per wicket in the SCG Test.

Australian Associated Press