Thompson will lead the line for the Paisley side when they take on Celtic in Sunday's semi-final at Hampden.
The odds are firmly stacked against Danny Lennon's team going on to claim the trophy for the first time having lost their last eight games to the Hoops by an aggregate score of 22-0.
But that has not stopped boyhood St Mirren fan Thompson from dreaming of becoming a poster boy like the Scottish Cup-winning side of his youth.
Thompson, capped 16 times for Scotland and the owner of a full set of domestic medals from his time with Rangers, told Press Association Sport: "It would mean everything for a club like St Mirren to reach a major final. I was there in 1987 when the team won the cup.
"I used to idolise those guys and their posters were up on my wall. It would be excellent to think we could repeat history and that I could become one of those guys for some kids.
"If we did win the cup with St Mirren, I guess it would jump right to the top of my achievements in my career. That's purely because we are not expected to win.
"Growing up as a supporter, it would mean everything. But we need to beat Celtic first before we can think about that."
The enormity of the task has perhaps grown a little bigger after Thompson and his team-mates took another severe dent to their confidence with last weekend's toothless display in a 4-1 home defeat to Ross County.
However, Thompson added: "With it being a one-off game and a cup semi-final this weekend, we can put the league to bed for a week and be positive."