IT is every boy's dream:

plucked from obscurity to play for your country against one of the top teams in the world and one of the heroes of your developing years. For Adam Ashe, every one of those elements of the perfect world have just come true.

He has been selected for his debut cap when Scotland play South Africa in Port Elizabeth tomorrow, one of four changes to the side that beat Argentina in their last match. He comes straight in at No.8 in place of Kieran Low, who is unavail­able because clubs in England refused to release players for the game.

The other changes involve Chris Fusaro, the Glasgow flanker, replacing Blair Cowan, who has been similarly restricted, while Tim Swinson and Henry Pyrgos start at lock and scrum-half in place of Jonny Gray and Grayson Hart, who drop to the bench to "balance the workload", as Vern Cotter, the head coach, put it.

A few days ago only a real rugby enthusiast would have known about Ashe in any detail: probably no more than a few dozen people in Scotland, outside his immediate family and the coaches dealing with him at the Scottish Rugby Union and Glasgow Warriors. Now he has been named to start for Scotland before he has started a professional game.

He was plucked from his work on a scholarship training programme with the Canterbury international high performance unit into the Scotland squad only last week but Cotter, who admitted he has never actually seen him play, also stressed that he is utterly confident from what he had seen in training that the player would handle the sudden promotion.

Ashe had just finished training in Christchurch last week when Kenny Murray, one of his coaches at the same facility, called him over and raised the possibility that Scotland might be on the horizon. Later that night, Gregor Townsend, his head coach at Glasgow, rang to confirm the inter­national interest and, the following morning, Gavin Scott, the Scotland team manager, rang to make it all official.

"I was a bit shocked but it was a fantastic feeling," he said shortly after learning that the squad call-up had turned into a spot in the starting XV. "I told my mum and dad and they were shocked as well. That is the only downside: I don't know if they are going to be able to get out here. They had already booked a holiday in Tenerife [but] my dad [George] said they may have to try to catch the game in the airport waiting to fly out."

Ashe's promotion is not entirely surprising. He had been marked out as one to watch as a teenager and had been pushed into the Scotland Sevens team in the World Series when he was still only 18. Indeed, he is the only one of the Scotland squad who has played in the Nelson Mandela Stadium in Port Elizabeth: the South African leg of the tournament was staged there the year he was playing.

After turning in a starring role in last season's under-20s campaign, this was widely expected to be his breakthrough season until it was ruined by a persistent hamstring injury that seemed to clear up three times before coming back to strike him down again. In the end, it has, indeed, been his breakthrough season, only he short-circuited all the boring playing-for-his-club bit and went straight into the national side. "It was really good to go over to New Zealand in the off-season in Scotland," he said. "I got a lot of game time, which really helped me."

Cotter was confident the youngster will deliver. "He has great qualities as a loose forward and a rugby player," he said. "It is an opportunity for him and I don't think 20 to 21 is young any more on the big stage. I am really confident that he will play well. If you look at the context of this game, it is important that it is about giving guys like him chances.

"I have not seen him play but he has impressed me with the training I have seen. He has adapted well, he listens and you can see he is a natural athlete. He is hard-working too, so he has all the qualities of a top loose forwad."

As for the other changes, Cotter had deliberately held Fusaro back to keep him fresh for this game, while the omission of Gray and Hart is more a case of starting the two players who are relatively fresh - they played only the final quarter in Cordoba - and resting those who dogged it out for an hour before that.

"It is very positive having these younger players who want to come through," he said. "I was impressed with Grant Gilchrist's captaincy last week. As a young man he took his responsibilities well and he has a group of young players around him. There is a generation of young athletes coming through who want to carry the jersey."