Argentina flyhalf Santiago Carreras punished an undisciplined Australia with 23 points off the tee as the Pumas held on grimly for a 28-26 win in Sydney on Saturday to breathe new life into their Rugby Championship campaign.

A try-fest beckoned in afternoon sunshine at Sydney Football Stadium but Argentina needed only one through captain Julian Montoya, with Carreras doing the damage with seven penalties and a conversion in front of a sell-out crowd.

A week after letting a 14-point lead slip in a 28-24 defeat to Australia in Townsville, Argentina saw most of a 21-point advantage erased in the final quarter as the Wallabies roared back through two Filipo Daugunu tries and another for Andrew Kellaway.

James O'Connor's conversion of Daugunu's second try put the Wallabies within two points in the 80th minute but their final stand ended after 11 phases with an errant pass.

The Pumas swooped on Max Jorgensen at the Wallabies' try-line to claim a penalty and close out a rousing win after having their hearts broken in Townsville.

"It was so emotional in the last 15 minutes," said Carreras, who slotted all eight of his point-scoring kicks.

"It was such an amazing game to watch [for the crowd]. I'm really proud of the boys for this win."

Australia came to Sydney with momentum after Angus Bell scored a try six minutes after the final hooter in Townsville to beat the Pumas.

But the hosts were left to rue another slow start against the South Americans.

"Absolutely spent. Devastated," said loose forward Fraser McReight.

"A credit to Argentina. We did the same thing last week. Gave them a big head-start and they're a great team.

"The effort from the lads to dig in especially in that second half, to come back from where we were ... Just spent." (Reuters)