Murchie Jr has the chance to make his Test debut as a replacement against the Springboks at Murrayfield as the Scots attempt to ensure that they avoid a daunting World Cup draw in 2015.
One of the proudest onlookers will be relative Ian Murchie, who laid his body on the line for his country for no reward or official recognition. He had hoped to claim a long-term place in the side when he lined up at centre against Argentina in 1969 on the first Scotland tour to South America, but his big-stage future was wrecked when he shattered a shoulder, thanks to a horrendous high tackle by the notoriously tough Alessandro Travaglini in Buenos Aires.
In these days, SRU officials refused to award caps for matches against Argentina because they were not deemed worthy rivals. Not only did Murchie Sr – now retired and living on the Isle of Arran, miss out – but he did not recover sufficiently to be considered for any subsequent full international.
Ian, a cousin of Peter's father Finlay, admitted yesterday that he was thrilled that the family name will at long last be recognised in the Scottish rugby annals.
Andy Robinson, the Scotland coach, has given Peter his chance in place of Max Evans and the youngster is likely to be deployed during the final half-hour or so on Saturday.
Murchie Sr said: "I have been following the fortunes of young Peter since he signed for the Warriors and he has certainly made a big impression this season, especially with his ability to play in so many positions.
"It was great to see him being included in the provisional squad for the autumn Tests and it is very exciting that he has now been given a great opportunity to make his international debut. It will be fantastic to witness a Murchie earning a cap at long last if he gets on."
Peter said: "My dad has told me about his cousin Ian and what a good player he was. There will be lots of Murchies, particularly from the Ayr area, at Murrayfield on Saturday, which will mean a lot to me.
"When the team selection went up on the board earlier in the week I only looked at the starting XV, and it was a few seconds before my eyes scanned the subs. My heart skipped a beat. It was a nice surprise: a brilliant feeling.
"I think my hard work at dealing with high balls has helped me a lot over the past few months. I also think my tackling and pace has improved. I am now in my fourth season at Glasgow and I will always be grateful to [former head coach] Sean Lineen for spotting me and researching my eligibility to play for Scotland.
"Facing the South Africans will be a massive challenge. They are very, very physical; when you face Springboks, you know what you will get."
Robinson said: "Peter has had a fine start to the season with Glasgow and his desire to dominate in aerial combat has been a factor in selection. He will prove very useful if or when there is a battle of the high balls. He is a very good young player and this is his big chance to step up."