This is virgin territory for the hosts while their Scottish opponents are chasing history of their own - bidding to be the first away semi-finalists to advance to the final and win back-to-back titles.
Connacht secured a 14-7 win when the sides met in the final round two weeks ago but Lam is expecting a more serious test from Gregor Townsend’s outfit this evening.
“We are under no illusions when it comes to the challenge we face against the defending champions Glasgow who are stacked with players with plenty of experience of Test-match and knock-out rugby,” said Lam.
“We know they will be much stronger than they were two weeks ago, but if we channel our physicality and excitement into our game, we will be able to meet that challenge head on.”
Lam has made one change to the side that won at home two weeks ago, with the more experienced Eoin McKeon taking over from Academy flanker Sean O’Brien who moves to the bench.
The Glasgow side is markedly different from their last trip go Galway.
Scottish intentional Sean Lamont starts on the left wing for Lee Jones, Mark Bennett takes over from the injured Alex Dunbar while Henry Pyrgos starts for Ali Price. In the pack Zander Fagerson replaces the suspended Sila Puafisi, and in a rearranged back row, Ryan Wilson moves to the blindside for Rob Harley, with Simon Favaro at openside.
“There is no doubt we will be under pressure,” says Lam,”and that is where our relations and culture come into it. All the learning will come into this game.”
Despite the significance of the tie Lam has not changed the squad’s normal weekly routines - indeed, yesterday’s captain’s run was conducted in “casual clothing” because “everything should be ticked off by then”.
The coach continued: “There is no doubt we have over-achieved in what we have done. To be in this situation just highlighted the only way to win was to treat the week as a normal week, that is how it has always worked - nothing special, no camps - just another day and another game that we have a great chance to win.”
With the much-malinged west of Ireland weather looking to dampen the occasion, Lam says Connacht are prepared for the worst.
“Whatever the conditions we will just have to adjust. But we have to fire shots. The object of the game is to score more points, to do that you have to have something up your sleeve, and we’ll have that all right.
“The weather is changing - what gives us a lot of confidence is the last time out we didn’t get the weather we wanted and we adjusted. Now it’s a case of whatever the weather, we can deal with it. “
Lam will be is looking for a sharper attack to unlock the Glasgow defence, and another brilliant defensive effort to contain the Scottish internationals and the rampaging Nakarawa.
Meanwhile,Townsend admits losing to Connacht was the best thing that could have happened to Warriors’ Guinness Pro12 defence.
He reasoned: “You learn more from defeat. You do get confidence from victories but you find out how to be better after a loss.
“Things get put through the magnifying glass.
“We’ve had two weeks’ preparation to put things right. It would have been better for the club and our supporters to have been at home but having that defeat has really sharpened our focus ahead of this weekend.
“Our preparation has been better than normal because the team we just lost to and who we want to put a few things right against is who we play in the next game. We will learn from where we could be better and try to get our strengths out.”