The home side were only able to score a solitary try two minutes from time when the result was already sealed as the tourists led by Cory Hill rose to the occasion as the Dragons captain promised.
On paper, there was a huge gulf in experience between the grizzled Pumas pack and Wales' callow eight with only 65 caps among them.
Ross Moriarty was the most experienced player in the starting eight with 21 appearances before last Saturday, while new captain Cory Hill, with 16, was the only other forward in double figures.
The scintillating form of Jaguares, their Super Rugby feeder team, seemed to leave the likes of Tomas Lavanini and Marcos Kremer ready to wreak havoc. But right from the off, the capacity crowd in Estadio San Juan del Bicentario had little to cheer as their traditional strength - the set piece - was smothered.
Daniel Hourcade’s charges were second-best at the breakdown and found themselves up against a clinical Welsh back row featuring the outstanding Ross Moriarty.
Indeed, Wales’ magnificent defensive display against Argentina, making 201 tackles to shut down Los Pumas was led by new Dragons recruit Ross Moriarty, who managed a remarkable 26 tackles, with fellow forwards James Davies and Adam Beard, who managed 17 apiece next in the tackle count.
Dragons Head Coach Bernard Jackman says the typically abrasive performance by Moriarty was the exact kind of showing they expect from the former Gloucester man and why the region worked so hard to sign the 24-year-old back row.
Moriarty joins the Dragons on a two-year deal this summer after a final frustrating campaign at Kingsholm as he returned to fitness after a back injury suffered in the first game of the 2017 Lions tour to New Zealand.
He played just five times for the Cherry and Whites and joined Richard Hibbard in swapping playing in front of the Shed with the Hazell for the forthcoming campaign.
However, any doubts about his back problems have been extinguished by two strong back-to-back displays for Wales against South Africa and Argentina, with Jackman pleased to see his marquee signing back to form.
"Ross gives you unbelievable abrasiveness on both sides of the ball. Players like that are hard to get and if you can't win collisions then this game is hard, and he wins them in defence and attack.
"There was a genuine reason why he was a little bit off," said the Irishman. "There was the injury and not having a pre-season, then leaving his club wasn't as straightforward as normal, then he played in the Six Nations without any game time.
"Now we see him after a 'pre-season' at the end of the season with Gloucester and he has played two 80 minutes, showing exactly the type of player we signed. That was good to see.
"It's great for us as a group to have someone like that who we would like to think will go to the World Cup and play a big role."
Fellow Dragons back row Aaron Wainwright made his debut against Argentina, with the 20-year-old Dragons graduate winning his first international honours just eight short months after his professional debut.
"It's brilliant for Aaron and shows that there has to be some kind of pathway for those late developers," said Jackman.
"Those that miss out on Wales Under-20s and feels that their chance has gone, it's not. Aaron has gone from Cardiff Met to here and is now capped for Wales in their most competitive area (back row).
"After what Aaron did over the course of our season, he has deserved this. He has been outstanding and what a way to finish his first season of pro rugby.
"He is a straightforward guy, so honest and such a good athlete. It's been good to see him, Elliot Dee, Cory Hill, Hallam Amos and Ross play so well – it's one thing being capped but another to make the most of those minutes."
Hallam Amos made a highly memorable contribution to open up the Argentina defence for Wales' first score against last weekend, watch it again below courtesy of Rugby Pro. Hopefully he'll get another chance to impress with the Wales team announcement for the second test revealed tomorrow..
