Pathum Nissanka and Dimuth Karunaratne survive three overs before lunch, going 0-8.
The session goes to Sri Lanka, which took five ports and restricted the Australians to 364, after which they resumed to 5-298.
Debutant Prabath Jayasuriya was the Sri Lankan star with the ball, taking 6-118 from 36 overs.
Steve Smith finished with 145 not out, while Marnus Labuschagne made 104 yesterday before being perplexed.