AT first glance, Dundee United’s pre-season tour of Germany in the summer of 2013 didn’t promise much. There was a 4-1 defeat to Union Berlin, a 2-0 reverse to Energie Cottbus and a 3-1 setback to Spanish outfit San Roque. But there was at least one shaft of light. Stuart Armstrong well recalls the debut of a 19-year-old left back called Andy Robertson.

“I remember playing my first game with him out in Germany, a pre-season game,” said Armstrong. “He was just a young boy, playing left back with a lot of energy. It is amazing to think that boy is now a Champions League finalist.”

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Robertson had just a season of first-team football under his belt by then, turning heads with his performances as an ever-present for Gardner Speirs’ Queen’s Park outfit which gave Rangers a game or two en route to the League Two play-offs. In Kyiv on Saturday he will become the first Scottish player since Paul Lambert in 1997 to start a Champions League final and Armstrong knows he will treat his date with destiny against Cristiano Ronaldo and co the same way as he would a run of the mill away match in the Scottish game.

“It is an incredible achievement,” says Armstrong. “I watched the semi-final against Roma and sent him a message the next day. It is amazing to think that he is going to be walking out in the Champions League final and great to think that he could win it and come home with a medal.

“The thing I love about Andy is no matter whether he is playing Ross County away or Real Madrid in a Champions League final, he always plays the same way, with the same level of enthusiasm. He has been terrific. I was really proud to see him move to Liverpool and now he is a mainstay in that team.”

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If there is a lesson for the rest of Scottish football, then it is simply to dream big. “Does it prove that other Scottish players can be a success down there?” said Armstrong. “Well, he has certainly showed that because he has been a major success.”

The news that Armstrong had pulled out of Scotland duty against Peru and Mexico this week, complaining of a hamstring tweak, came as little surprise to those who caught up with him in the immediate aftermath of the midfielder completing the double treble with Celtic at Hampden Park. While in one sense this player – who proved his value to the Scotland cause in the latter part of the Gordon Strachan era – could be said to need games, one thing he certainly doesn’t need to do is compromise his fitness for next season. With the lack of a proper lay off last summer blamed for the hernia operation he required in mid-season, a trip like this is hardly ideal for Armstrong, who will be back in training camp by mid-to-late June in an attempt to hit the ground running for Celtic’s Champions League qualifiers.

“In January I was obviously out with an operation, I was out for a couple of months coming back, so it has been quite a frustrating six months for me. But to be fit again, come on and enjoy the final with the boys, I felt great. Playing the tail end of last season, I was struggling physically.

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“To finally get that sorted around January, it took me a while to get back feeling myself, but I am feeling good now. It was nice to come on in the final and be involved and be a part of it. We had a fantastic season last season and we’ve been able to repeat that again.

“Maybe the performances, the fluidity, hasn’t quite been there so much this season but it is very hard to replicate that, what was obviously an amazing season for us. But when it mattered, we got the trophies in the end.”

If this campaign was a different mental challenge for the 26-year-old, it is easy to forget that the player had to bide his time to get a run of games under Brendan Rodgers in the first place. “Personally, last season wasn’t fantastic in every sense – people forget I wasn’t in the team until November,” he said. “So that was a different test mentally. While getting my place in the team and having a great season, getting the medals and the accolades and having a short summer, has been testing physically.

“But that is football. Every boy in this team will have injuries or testing times in their careers, that is how the last six months have gone for me.

“I don’t want to put too much pressure on myself for next season, it is just about making sure I am fit and trying to take my chance when it comes. It isn’t about proving a point. You sometimes take for granted when you are physically fit and well, and the frustration which comes from being injured. Staying fit and injury free is something I want to be.”