Wales slumped to their fourth defeat in five games under Gary Speed in Wednesday's friendly against Australia.
Tim Cahill struck for the Socceroos just before half-time when the Everton man was given the run of the Wales area to convert a cross from Luke Wilkshire.
Robbie Kruse added a second when Wales goalkeeper Wayne Hennessey could only parry a low cross into his path.
Darcy Blake's header with eight minutes remaining gave Wales hope but Australia rode a late flurry in Cardiff.
Wales must now prepare for a tough Euro 2012 qualifier double-header, against Montenegro at the same Cardiff City Stadium on 2 September before facing England at Wembley four days later.
Neither goalkeeper was troubled in a quiet first quarter as both sets of players tried to knock off some pre-season rust.
Australia at least hinted that there was more to come from Holger Osieck's visitors, while Wales lacked penetration the few times they ventured over the half-way line.
Chris Gunter, standing firm in a Wales defensive wall, did well to head clear Wilkshire's free-kick, before Carl Valeri wasted a promising Australia break by scuffing his shot harmlessly wide.
There were a few ironic cheers from a sparse 6,373 crowd when Wales won their first corner in the 21st minute.
But Craig Bellamy earned heartfelt applause moments later, as the Manchester City forward cut in from the right and fired a shot at goal that spun away off an Australian back.
But on 35 minutes Hennessey was relieved to see Wilkshire's pile-driver cannon off his near post after the Dinamo Moscow man was allowed to advance on the Wales goal.
Wales had a penalty claim waved away when Gareth Bale, playing his first international game for 10 months, was sent through by Joe Ledley before tumbling when he came together with Brett Emerton.
But Australia counter-attacked swiftly and Wilkshire crossed from the right for the unmarked Cahill to thump home right-footed from just outside the six-yard box.
Wales survived an early scare after the restart when they failed to clear and Kruse saw his snap-shot saved by Hennessey's shins.
The danger was not over as the woodwork again came to the rescue of the Wales keeper when Valeri stabbed the rebound onto the post.
Jack Collison, on for captain Aaron Ramsey at half-time, produced Wales' best effort on goal as the West Ham midfielder cut back on the right and lofted a left-foot shot just past the far post.
But that small encouragement was shoved rudely aside as Australia broke again to double their lead.
Cahill found Scott McDonald overlapping on the right and the Middlesbrough man sent a low cross into the Wales area.
Hennessey managed to get a hand to the ball but only succeeded in pushing it into the path of Kruse, who had an open goal in front of him.
Wales were given a lifeline eight minutes from the end when Ashley Williams flicked on a corner for Blake to head past Mark Schwarzer for his first international goal.
But the home side were unable to breach the Australia defence a second time and must now prepare for next month's competitive clashes with Montenegro and England.
Wales: Hennessey, Gunter (Matthews 62), Taylor, Vaughan (Allen 70), Gabbidon (Blake 46), Williams,Ramsey (Collison 47), Ledley, Bale, Earnshaw (Morison 62), Bellamy. Subs Not Used: Myhill, Eardley, D Collins, Robson-Kanu, King, Tudur Jones.
Goals: Blake 82.
Australia: Schwarzer, Wilkshire (Kruse 46), Neill, Spiranovic, Zullo (Sarota 83), Emerton (Williams 48), Kilkenny, Valeri, McKay, Cahill (Troisi 70), McDonald (Jedinak 90). Subs Not Used: Federici, DeVere.
Goals: Cahill 44, Kruse 60.