Neath-Swansea Ospreys hooker Huw Bennett is one of six changes to the side team lost the first Test 44-50 in Tucuman last weekend, and he's relishing the chance to impress coach Mike Ruddock in the absence of first-choice Wales hooker Robin McBryde.
"Very rarely do you get the opportunity to get revenge within a week, and there's a feeling going around that we have to prove ourselves," the 21-year-old said.
"You're only as good as your last game and we have to prove that we're better than what we showed last week."
Bennett was confident the new Welsh defence system - so good in a 42-0 win over the Barbarians but so bad in Tucuman - would work this weekend.
"Griff (defence coach Clive Griffiths) has brought in this new system, and it's an ideal system against this sort of team, because it's very intimidating. It's very aggressive.
"But it's new and it will take time to gel - it takes a lot of concentration on the field."
The powerfully built Bennett is having a week to remember - he turned 21 last Friday, earned his sixth cap as a 70th-minute replacement in Tucuman and gets an eagerly awaited start in Buenos Aires on Saturday.
"It's a good time to put my name on the map," he said. "It's a chance to have a full game of rugby and to learn from that.
"For myself, if you want to learn about scrummaging and frontrow work, they don't get any better than Argentina."
Bennett said it felt strange going head to head with Pumas legend Federico Mendez last weekend.
"I remember him knocking out Paul Ackford at Twickenham when he was only 18 or 19," he said. "I was only about eight at the time, so it was strange coming up against him in a place like Tucuman."
With the likes of Gavin Henson cementing a spot in the Wales backline and Bennett getting the nod up front, the youngsters are making their presence felt on this tour.
"It's great to be on tour with the likes of Gareth Llewellyn, who has so much experience," he said. "If he was playing senior rugby in 1986-87, I was three years old - that's just mad!"