Wales coach Rob Howley felt his players paid the price for a sluggish first half as Australia claimed a 32-8 victory in Cardiff.
Australia breezed into a 20-3 half-time lead which would have been far greater had they taken all their chances.
Wales mounted a belated comeback late on but Australia's superiority was reflected by a handsome five to one advantage on the try count.
"It's very disappointing and very frustrating," said Howley, who is in interim charge of Wales with Warren Gatland on leave ahead of next summer's British and Irish Lions tour to New Zealand.
"I think the possession and territory at one stage was 80 per cent, so it wasn't what we expected.
"We never had a foothold in the game and, when you give a side that's very cohesive and been together a long period of time, you see how effective they can be with speed of ball in the contact area.
"We were unable to influence that area and get a defensive line set and, in fairness to Australia, they took every advantage they could and created a number of tries.
"It was much improved in the second half because we did have a foothold.
"But then you're influenced by the scoreboard and start playing too much rugby in your own half."
Wales' remaining autumn programme sees them play Argentina, Japan and South Africa in Cardiff.
And Howley insisted he saw enough positive factors in the second half to go into those Tests with confidence.
"I saw enough detail (to be optimistic)," Howley said.
"The second half share of possession was nearly 50/50 and we grew into the game.
"That first half was not so much the speed or intensity which we traditionally struggle with first up (in the autumn).
"It's how good the Wallabies were and how effective they were in the contact area."
Wales were already without several key players, including skipper Sam Warburton, Alun Wyn Jones, Taulupe Faletau and Liam Williams, when they suffered another blow close to kick-off.
Lions centre Jonathan Davies was omitted after feeling a tight hamstring in the hope that he will be fit to play against Argentina next weekend.
But Rhys Webb's presence in the rest of the autumn series is in jeopardy after the scrum-half suffered suspected ankle ligament damage.
"He's being assessed medically," Howley said.
"He's been cleared out in the tackle and his ankle has swollen.
"I don't think there's any breakage, but it looks as if ankle ligaments have been damaged in some way."
Australia coach Michael Cheika was delighted with his side's performance on the first leg of their northern hemisphere tour.
The Wallabies have not completed a 'Grand Slam' in Europe since 1984, but they now face Scotland, France, Ireland and England in the next month.
"I thought we prepared well during the week and the boys believed in that preparation and went out there and played that way," Cheika said.
"Our attitude was that we wanted to work hard and put our bodies on the line.
"It was a team effort, a good win, but that's the standard we need to remain consistent with.
"We have to take that into next week because we have to keep on improving.
"We need to get more battle-hardened because it is only going to get tougher the more the northern hemisphere teams get games under their belt."