Argentina lock Tomas Vallejos hopes the Pumas renowned scrummaging power will prove decisive when they face a weakened Wales front row on Saturday.
Wales will be without tighthead prop and scrum anchorman Adam Jones, sidelined because of a knee injury, when they face the powerful Pumas in a full international at the Millennium Stadium.
The loss of the 2009 British and Irish Lion is a major blow to Wales and now interim coach Rob Howley must decide whether to call up Jones' uncapped deputy Aaron Jarvis or switch loosehead prop Paul James to the other side of the scrum.
All this disruption is the last thing Wales need against an Argentina side who, while results didn't go for them during their maiden Rugby Championship campaign still pushed Australia and South Africa close.
The 27-year-old Vallejos, who has a foot in both the Argentina and Wales camps having recently joined Welsh regional side the Scarlets, made no attempt to disguise the Pumas' gameplan on Monday.
"We have a massive belief in our scrum, it is one of the foundations of the team," said the former Harlequins forward, called into the squad as a replacement for the injured Patricio Albacete.
"If Jones plays or not it will not change our approach. We will still believe in our scrum and it will play a massive part in the game for us and we know Jones has been a massive player at the top level."
Among the Scarlets teammates set to become opponents for Vallejos on Saturday is giant wing George North.
"George is a big player, the thing that surprised me is he is a massive guy and he is physical, but he also has skills and it makes him a very special player," Vallejos said.
"I will be telling some of our guys in the backline we need to keep a close eye on him."
Meanwhile Vallejos has an additional motivation for wanting to win this weekend - bragging rights in the Scarlets' dressing room.
"It would be fantastic to win the game especially with me playing here, it would be funny for me to be able to do some jokes in the changing room and I am really looking forward to it."