As he did in Florence almost two years ago, Donaldson entered the game in La Plata in the final minutes and was called upon for a crucial play, with a penalty kick on the buzzer.
With this shot much easier than in the Italy game, the 25-year-old playmaker made no mistake to steer Australia to a 20-19 victory, which was their first in the four-team tournament.
Donaldson said he welcomed another opportunity to be a match-winner, and didn't give his wayward kick against the Italians a thought.
"I didn't go back to the Italy game," Donaldson said.
"There's always pressure in those moments, they're big moments in Test match footy, but as a player, as a kicker, you thrive for those moments, they're the moments you want.
"I've said to people before, I'm probably lucky that I went through that moment in Italy, I think it's made me grow as a player and as a person.
"We do a lot of work throughout the week, put ourselves in moments as kickers, so when we come to the game, we're ready for it."
Jake Gordon goes over for the first of two Wallabies tries in the win over Argentina in La Plata. (AP PHOTO)
The Wallabies spent a quiet day savouring the win over last year's World Cup semi-finalists, with Donaldson unsure if it would be a "turning point" after two heavy defeats to South Africa to open the Rugby Championship.
"It's hard to say, to be honest, it's just a win," he said.
"Any win away from home is huge, especially against Argentina - the crowd was pretty hostile, the weather conditions were tough, but the boys put in a great shift.
"We've got a long way to go as we probably weren't at our best again.
"So turning point, yeah, not too sure, but we're definitely going to take some confidence out of that game and momentum and springboard into this week and then into the two All Blacks games."
The tourists have moved on to Sante Fe in northeast Argentina, where the teams will play on Saturday afternoon (Sunday 5am AEST).
After pouring rain in the last two Tests, in Perth before La Plata, the forecast is for 27 degrees and sunshine.
While they smartly played to the conditions and demonstrated their improved handling and defence under new coach Joe Schmidt, Donaldson said a dry track would allow them to add more variety to their attack.
But he warned that the Pumas, who put 38 points on New Zealand to win their Rugby Championship opener, would be able to do the same.
"As backs, we've had some set plays there for a while, but we haven't really got through many of them, obviously with the weather as Perth was pretty horrendous weather, as was the other night.
"Hopefully this week it's some nice weather and we can showcase our skills but then off the back of that, Argentina have some silky backs as well, so we're going to have to be on our toes with them."
