Michael Clarke stood resolutely behind Australia's unpopular rotation policy despite admitting selection changes contributed to their Gabba nightmare yesterday.
Captain Clarke labelled it a "horrible day" as his men were routed for 74 before Sri Lanka (6-75) chased down the target in 20 overs for a four-wicket win and a 2-1 series lead.
The day-night match in Brisbane was finished at 6pm local time as a disappointed crowd of 20,271 traipsed home in the daylight.
It would have been over much earlier, well before the scheduled tea break, if not for a last-wicket stand of 34 by tailenders Mitchell Starc and Xavier Doherty - the only men to make double figures.
Clarke, who had no hesitation in batting first, was among three first-choice players who returned from a two-game rest after a 3-0 Test series whitewash.
Asked as he left the ground whether it was difficult for cricketers to maintain rhythm and confidence if they weren't consistently selected, he said: "Yeah, I can't doubt that.
"Today is an example of that.
"If you're playing well and winning consistently, it builds momentum, that's for sure. It's still no excuse for the way we performed."
But Clarke then staunchly defended the rotation policy at his official press conference, instead blaming poor shot selection and defence for the third lowest total in Australia's one-day history.
"When you bat like that you're not going to win many games of cricket," he said.
"My opinion hasn't changed on, let's call it once again, the rotation policy. Our performance today was very poor.
"We let ourselves down, we let the people down who came to watch us.
"I think our cricket throughout the summer has been pretty consistent - today is, for sure, our worst day."
The loss also exposed Australia's frailty against quality swing bowling.
Led by the mesmeric Nuwan Kulasekara, the Sri Lankan pace attack completely embarrassed the hosts - reducing them to 9-40 in the 19th over when captain Mahela Jayawardene had thought 220 would be a par score.
In scenes reminiscent of the carnage in Cape Town 15 months ago when Australia's Test team were bowled out for 47 by South Africa, man-of-the-match Kulasekara took 5-22 and Lasith Malinga 3-14 as Australia failed to counter the brilliant mixture of swing and seam.
Sri Lanka's batsmen also had their problems with the sideways movement, crashing to 4-37 as Mitchell Johnson dismantled their top order with 3-4 from his first eight deliveries.
But Johnson was inexplicably taken off after the tea break while Australians were also left to rue missed catches by Clarke, George Bailey and David Warner.
It was only the determined rearguard by Starc (22 not out) and Doherty (15) that saved Australia from more embarrassment.
When Doherty leg-glanced his first ball to the boundary, Australia passed the lowest total by a recognised Test nation - 43 endured in South Africa by both Pakistan (1993) and Sri Lanka (2012).
The spinner's last boundary ensured they crept beyond 70 - which Australia made in 1977 in England and also in 1986 against New Zealand in Adelaide.
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