Victory over Indonesia in their final Toulon Tournament group game today would almost certainly see the Under-20s set up a last-four clash with the Three Lions.
That showdown would take place just 48 hours before the senior teams battle it out in in the World Cup qualifying crunch at Hampden.
Ralston was hoping to go to the National Stadium as a fan, but will still be in France if Scot Gemmill’s side reach the semi-finals for the first time in 22 years.
The attacking full-back made his first start for the Hoops in their win over St Johnstone last month and was in the Scots side that beat Brazil three days ago.
“And if that happens, we will deal with it. We would just go in with the same attitude.
“If I was back home I would definitely try to get a ticket and go along to the full team game at Hampden.
“I support Scotland – it’s my national team. But if we go through to the semi-finals in Toulon we will be in the Final or third and fourth place play-off then and that would mean we would still be here on Saturday. That’s the aim.
“It has been the stuff of dreams after my first Celtic start and then beating Brazil.
“I’ve been a Celtic fan all my life along with my family, so that was amazing.
“And then to come over here and have the experience of being away with Scotland and beating Brazil was outstanding.
A 2-0 win for Gemmill’s side today would mean only a freak result in the Czech Republic’s clash with Brazil could see them eliminated.
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