wru.co.uk and James Mortimer 11.Nov.2012Getty Images
Pumas captain Juan Fernandez Lobbe deservedly won the man of the match award with an inspirational performance. He led from the front as the Pumas won just their second game in Cardiff, 11 years after their first scalp.
A flat performance from Wales also places in jeopardy their chances of being seeded in the top four when it comes to World Cup rankings next month.
Wales were blunt in attack and looked a pale imitation of the side which claimed the Grand Slam earlier in the year. Despite leading 9-6 at the break, it was somewhat against the run of play as the Pumas dominated possession and territory but failed to convert pressure into points.
Lobbe was instrumental in creating the Pumas first try in the 55th minute with an exquisite off-load to Juan Manuel Leguizamon who replicated his captain's deftness to send Juan Jose Imhoff through a gap. The flying winger stepped Leigh Halfpenny and showed the Wales full back a clean pair of heels to score under the posts.
Fellow wing Gonzalo Camacho then got in on the try scoring act with a brilliant finish by the corner flag, riding Halfpenny's tackle to score a deserved try. Camacho was outstanding all day in defence and showed a lethal finishing touch, something Wales couldn't discover themselves.
In a scrappy first half there was very little structure to the game as Argentina dominated territory and possession but were unable to make their superiority pay as they lacked penetration.
Three first half penalties by Halfpenny, answered by a penalty by Felipe Contepomi and a drop goal by Nicolas Sanchez, gave Wales a 9-6 lead at the break. In a bruising opening half Wales lost both Jamie Roberts and Alun Wyn Jones through injury in an attritional contest.
Wales interim coach Rob Howley described his side's performance as "disappointing" as they slipped to a 26-12 defeat to Argentina.
Here's what Howley had to say on the defeat.
"International rugby is about doing the basics and in areas of attack and defence today we weren't as efficient as we should have been.
"Losing Jamie Roberts and Alun Wyn throughout the game didn't help but you have to cope with those changes.
"We struggled early on in the first-half with territory and possession. They dominated as they have done when we've played them in the past with possession and we defended particularly well in the first-half. When the game went to 12-6 we thought in the next 25 or 30 minutes we would kick on but Argentina showed great resilience to come back and took their tries particularly well.
"It's disappointing. We spoke about pace and intensity throughout the week and we struggled in the latter half of the game. I said to the players it's a test of character for everyone, coaches and management and we have to come back stronger.
"We've got three games to go, a hugely physical challenge with Samoa next week so it's important we get back on the training paddock and sort things out.
"International rugby is about scoring tries. It hasn't been a problem for us in the recent past but today as I say, we struggled with possession and territory.
"That was an area of concern in terms of struggling with territory and possession and not being able to put Argentina under the pressure we wanted them to, particularly in their 22 metre area.
"We have to work hard and be smart and there were areas today where we weren't smart. We have to improve all round.
"I thought our scrum started off particularly well and we got a platform but we didn't have the right attack in the right areas of the field. The territorial dominance was a bit disappointing today and that's an area we need to work on to put teams under pressure.
"We trained well all week. We spoke about the tempo and the pace of the game which is important when you play Argentina and we just didn't start well. That's something we need to speak about as coaches and players ahead of another physical challenge against Samoa.
"Injuries are a part of rugby. We had injuries coming into this game and we've picked probably two or three more. Whether there'll be available for next week we'll have to wait and see on medical opinion but that's the nature of the game.
"With injuries it gives an opportunity to others. Losing Jamie and Alun Wyn didn't help, they're two key members of our team but players came on and had a positive impact. We'll have to sit down and see where we are next week."