Once there was a time when he was almost blase about featuring in big matches, nonchalantly assuming there would always be another just around the corner. Now in the twilight of his career, the St Mirren striker is facing up to the fact tomorrow's Scottish Communities League Cup semi-final could well be his last involvement in such an occasion.
Thompson, 34 years old and out of contract in the summer, is not being unduly pessimistic about his side's prospects but there is an acknowledgment of the reality of the situation. To that end the entire Thompson clan, young children and all, will decant to Hampden for the game. Playing in the national stadium, for the team he grew up supporting, will be the fulfilment of a childhood dream and the striker is determined to wring every last piece of pleasure from the day.
"I think you cherish it more in the latter stages of your career," he said. "I am going to try to soak in as much of it as I can and store it in the memory bank as I don't know how many more occasions like this I will get. When you are younger, you can be a bit more flippant but you don't get to finals every year.
"I am going to take my kids in case we don't get back. They don't go to a lot of games as they can't sit still for more than two seconds. When I am an old man and talking about my career, I can tell them they were there. Both have been to Wembley; my boy Struan was at the FA Cup final [when Thompson was with Cardiff City] when he was less than three weeks old and Gracie, my daughter, was one-and-a-half."
Thompson recalls a similar experience. He was eight when St Mirren last won a major trophy, that Scottish Cup success in 1987 still fresh in his mind. The prospect of leaving a similar legacy to his heroes is enticing. "I grew up with posters of that team on my wall and I've still got a cup-winners' scarf in my loft. I idolised these guys and it would be nice to repeat what they did. If we were to win the cup, it would definitely go to the top of my list because of my emotional attachment to the club. It is no secret I love the club."
To have any chance, St Mirren will have to nullify Celtic's Gary Hooper. Marc McAusland knows that represents a massive task. "He is on fire," said the defender. "You can see from the interest in him how well he has been doing and Celtic think so much of him that they are knocking back bids. He plays on the shoulder and anything that comes in the box he can put in the net, so that emphasises how on our game we need to be. If we can stop him then we have a chance."