Sportal.co.nz 18.Nov.2012Getty Images
Samoan hero Lam, captain when his country defeated Wales in Cardiff 13 years ago and now their technical adviser, feels it is a dangerous game to write off an underdog.
Lam proudly looked on as Samoa toppled the reigning Six Nations champions 26-19 to avenge last year's painfully narrow World Cup defeat in Hamilton.
If left Wales facing a probable end-of-year Test series whitewash, given pending appointments with New Zealand and Australia on the back of conceding 52 points to Argentina and Samoa, while scoring just one try.
They have not beaten the All Blacks since 1953, suffering 24 successive defeats.
While New Zealand remain the game's dominant force, Wales are now clinging on to a place in world rugby's top eight.
"No-one is going to give them (Wales) a chance whatsoever next week, and rightly so, because New Zealand are number one and Wales have lost the last few games," Lam said.
"But that is the challenge of rugby and sport. You are up against it, but you never write off any team."
Lam's stunning tale of success against Wales has now spanned more than 20 years.
He played when Western Samoa, as his country was then known, shocked Wales 16-13 in a 1991 World Cup fixture, then skippered Samoa eight years later to another spectacular global tournament success in Cardiff, scoring a try during an epic 38-31 win.
And the 44-year-old former Blues Investec Super Rugby coach revealed how those past triumphs impacted on the class of 2012, who outscored their hosts 3-1 on tries and will not lack confidence for next Saturday's clash against France in Paris.
"This is really special for us," he added.
"I talked to the boys about 1991 and how we opened the gate to international rugby for Samoan rugby back then, and to present the jerseys to the players on Thursday night was very emotional for me.
"I think everyone in the past talked about us taking Wales by surprise when we beat them.
"But they lost last week to Argentina, and there was no reason for them not to be up for it. It was an important game for them, so it is pretty special for us to win like we did.
"Samoa is not a team about fame and fortune, it's not about money. Boys, given where they are based in the world, actually lose money when they come to play for Samoa. We are a people's team.
"We showed the boys a video of all the people back home in Samoa, and all the little kids, during our build-up, and it was quite emotional. It just reminded everyone of who we are."
There was no magic formula behind Samoa's latest Millennium Stadium triumph, just sheer unrelenting commitment and endeavour that underpinned another momentous victory.
"The boys put their bodies on the line, and to see them come through like that was just fantastic," Lam said.
"It is a great achievement to beat the Six Nations champions on their home ground. We had a clear structure and game-plan, and the boys brought the heart to implement it.
"There were a lot of things that mirrored the 1991 game. There was a lot of tension in the build-up. Everyone wanted a place in the team, and training was very physical.
"There was bit of tension in the camp, but that is exactly what happened in 1991. It brings the alertness to training, but also reminds the guys that we are not here for individual purposes - it is about the team.
"All you have got to do is have belief in what you are doing. The principles of rugby are exactly the same, it doesn't matter whether it is amateur or professional - win the ball, go forward, continuity, support and score tries."