KKR confirmed late yesterday that it was exiting the bid having examined Coles' accounts, following two weeks of due diligence, just hours after CVC said it was withdrawing.
The surprise departures leave four private equity firms - Carlyle Group, TPG, Blackstone and Bain Capital - still in the consortium bid for Australia's second largest retailer.
There is also speculation that main rival, Woolworths - Australia's largest retailer - is in talks about joining a possible buy-out of Coles valued at more than Aus$20 billion (£8.25 billion). And Wesfarmers, one of Australia's biggest public companies, has already offered Aus$19.7 billion (£8.12 billion) for Coles.
Coles put itself up for sale in February after a profit downgrade, following declining sales in its supermarket division.