Australia's Stirling Mortlock is confident he can overcome a shoulder injury before next week's Tri-Nations clash with South Africa.

Mortlock was hurt in last week's series opener in Christchurch as New Zealand beat the Wallabies 12-6.

"It felt like a totally different shoulder injury to what I had done before so I was a bit worried during the game and it was sore the next day," said Mortlock.

"But it's been getting less painful each day and my movement is coming back and the strength is almost there again.

"It feels more like bruising now but I'll still check with the doctor tomorrow. Everything's going well, I should be right to play by next weekend."

New Zealand host South Africa in Wellington on Saturday before the Springboks return to their training base in Brisbane for the 27 July test against the Wallabies.

And Mortlock expressed confidence that the world and Tri-Nations champions could improve on last week's performance.

"It was disappointing but I really thought our forwards played an exceptional game," he said.

"Our handling wasn't up to the standard we need but we're going back into camp (on Thursday) so we have time to improve on certain areas before next weekend."