Wales coach Gareth Jenkins says his side failed to meet the forward test of the Pumas in their record 45-27 loss.
We've learnt a lot, that we have to compete physically, have possession and play gain-line rugby
Wales coach Gareth Jenkins
"There were a lot of things different to last week and the better side won, for sure," he told BBC Sport Wales.
"Our line-out didn't work, the set piece was under pressure and we didn't have the same go-forward to compete.
"Argentina were purposeful, aggressive, physical and impressive - and they had all the ball. Playing defensive rugby tires you, we were off the pace."
Wales captain Duncan Jones was a forlorn figure after the Pumas battering in Buenos Aires.
"No excuses, they made it very difficult for us," he told BBC Sport Wales.
We had a lot of youngsters on this trip
Wales captain Duncan Jones
"We also caused a lot of problems for ourselves, but that's not to detract from the Argentineans, they deserved it.
"We had a lot of youngsters on this trip who will have learnt a lot, but today we're all very down."
Jenkins, still seeking his first win in charge of Wales, also felt that there could be long-term benefits from the tough tour.
"There will be positives and we'll go forward from here," he said.
"We've learnt a lot, that we have to compete physically, have possession and play gain-line rugby."