Hadden, as expected, failed to deliver any surprises ahead of the showdown with the Pumas, keeping faith with the side that squeezed past Italy 18-16 in St Etienne last weekend.
The bulk of the 22 selected played together in the three must-win group games as well as the warm-up matches prior to the World Cup, and have been showing signs of gradual improvement.
They will have to raise their game even more to worry the in-form Argentinians, but Hadden is confident in his starting XV.
“As usual, there was a lot of discussion about individuals, partnerships, units and the team, but we are getting to the stage where we have a group of guys who have played five games together in seven weeks,” he said.
“It made sense to go with a side that is prepared for this.
“We have made progress in those five games and we are expecting an even bigger performance this weekend.
“There are plenty of tools in the tool box. Now it is just a case of using the right tool, in the right place and at the right time.”
Arguably the biggest area of discussion for the selectors would have been the centre partnership, with Andrew Henderson fit again after a dead leg ruined his early part of the tournament.
But Hadden saw no reason to change the Rob Dewey-Simon Webster midfield combination that battled well against Italy. Henderson, who scored a hat-trick against Ireland in a World Cup warm-up, stays on the bench.
Elsewhere, Scotland’s record cap-holder Scott Murray is again left out, with Nathan Hines and James Hamilton the starting locks and Scott MacLeod on the bench.
The rest of the team picked itself, with Rory Lamont recovered from blurred vision he suffered against Italy to take his place at full-back.
Hadden’s men are looking to equal 1991 side, the only Scotland team to reach the semi-finals.