The price is a record for seats at any match other than a final, not just in rugby union but across all sports, says re-sale platform Viagogo, where the tickets were sold.
England almost certainly have to beat the Wallabies in the Pool A showdown at Twickenham to avoid becoming the first hosts of the tournament to be eliminated at the group stage.
Rugby fans are so desperate to see it that the re-sale price for the must-win fixture is curently higher than for seats at the competition's final.
The £4,000 price tag also beats the previous record for a non-final sporting event re-sold on the same platform: tickets for Andy Murray's 2013 Wimbledon semi-final, which fetched £2,800 each.
“This is the highest price ever paid for any non-final sports event, even outstripping prices for the final, suggesting fans are desperate to see what could be the greatest rugby game in recent history," said a Viagogo spokesperson.