Australia was miles away from where it should be in Sunday's six-wicket defeat at the hands of South Africa in Perth, says captain Aaron Finch.

Having been put in to bat, Australia could only muster 152 as the Proteas' bowlers enjoyed the early conditions, Dale Steyn the pick of the visitor's seamers.

Australia's total was its lowest in a home ODI against South Africa for 21 years and is a record seventh-successive defeat in the 50-over format.

And Finch acknowledged the performance was not up to scratch, while admitting it did not do enough with the ball either.

"[I am] disappointed, we didn't play anywhere near our potential," he said in his post-match on-field interview. "South Africa put us on the back foot early.

"It's an opportunity to learn and improve. We'll review the game, keep training and look forward to Adelaide.

"We were a bit careless at times, [we lacked the] attention to detail. We were off the mark slightly. 

"Everything has to go right to defend a small total. Full credit to South Africa they played nicely."

'Brilliant to have Dale back'

Understandably South Africa skipper Faf du Plessis was delighted with his side's start to the series, hailing the impact of the returning Steyn.

"Yeah, very good," he said. "We were exceptional with the ball and in the field. A very good day in the office.

"It's brilliant to have Dale back. It's good to have that x-factor in your bowling attack. 

"I'd have liked us to be a little more clinical, maybe eight, nine wickets but we'll take the win."