Both sides have already qualified for the semi-finals.
Defending two-time champions Australia, on a 25-game unbeaten run at the World Cup since losing to Pakistan during the 1999 tournament in England, made one change to the side that beat Ireland by nine wickets in Barbados on Friday with the previously rested Nathan Bracken returning in place of Stuart Clark.
But while Australia were fielding their first-choice side, Sri Lanka were under strength.
The 1996 champions, were without injured fast bowler Lasith Malinga for the second successive match.
However, they also made two changes to the team that beat New Zealand by six wickets here Thursday, with left-arm quick Chaminda Vaas and off-spinner Muttiah Muralitharan, two of their leading wicket-takers and stars of the 1996 World Cup-winning team, omitted.
Their places were taken by leg-spinner Malinga Bandara and pace bowler Nuwan Kulasekara, both of whom were making their debuts at this tournament.
Sri Lanka's strategy had the effect of denying Australia's batsmen a fresh look at both Vaas and Muralitharan ahead of a possible semi-final or final match.
Sri Lanka's only defeat in this tournament so far was a one-wicket Super Eights loss to South Africa in Guyana on March 28.
Australia: Adam Gilchrist (wk), Matthew Hayden, Ricky Ponting (capt), Michael Clarke, Andrew Symonds, Brad Hodge, Michael Hussey, Brad Hogg, Nathan Bracken, Shaun Tait and Glenn McGrath. Coach: John Buchanan.
Sri Lanka: Upul Tharanga, Sanath Jayasuriya, Kumar Sangakkara (wk), Mahela Jayawardene (capt), Chamara Silva, Tillakaratne Dilshan, Russel Arnold, Farveez Maharoof, Nuwan Kulasekara, Malinga Bandara and Dilhara Fernando. Coach: Tom Moody
Umpires: Billy Doctrove (WI), Aleem Dar (Pak) and Third umpire: Mark Benson (Eng)
Match referee: Mike Procter (RSA)
Pitch report: Much will depend on how much the pitch has been watered with residual moisture likely to assist pace bowlers. However, blue skies overhead should reduce the likelihood of swing movement.
Weather: Chance of a thunderstorm. Temperature rising to 87 degrees Fahrenheit (31 degrees Centigrade).