Andreas Thom on memories of his past life at Celtic and why Borussia Moenchengladbach should not be underestimated

First, he spent a few minutes soaking up the atmosphere being beamed over from Celtic Park, rather than Borussia-Park, even turning the sound up on his plasma TV as the supporters raised the roof for Zadok the Priest and You'll Never Walk Alone.

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"When the Champions League is on I tend to watch the German teams more," Thom told Herald Sport last night. "But to be honest I watched the Celtic game for the first five minutes or so before the game because I have such good memories of when the supporters are singing. I put the volume up to a high level."

Who knows what Thom's neighbours in the German capital made of that, but it wasn't until he caught up with highlights of the 3-3 draw against City that he must have wondered whether he should have kept faith with the footage from Glasgow for a while longer. So aggressively and economically did Brendan Rodgers' side press the game and use the ball in those early stages against Pep Guardiola's side that Thom recognised an almost Teutonic efficiency in their game.

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"I don't have the chance to watch Celtic playing in domestic Scottish games, I can only watch them in the Champions League," said the former German international, part of the Euro 92 squad which finished continental runners-up. "But I was very impressed with the result and the kind of football they played against Manchester City. It was very good, almost a German style. The supporters I think were very surprised that they managed to get such a good result against such an expensive team."

The rebuilt Celtic Park was just bedding in when Thom, plucked from Bayer Leverkusen for a then club record fee of £2.2m back in 1995, was a player under Tommy Burns. Now it is one of the most famous arenas in Europe and the big question for this current group of Celtic players is whether a young Borussia Moenchengladbach, who are likely to travel to Glasgow without their three top strikers, Raffael, Thorgan Hazard - brother of Chelsea ace Eden - and Josip Drmic, will be able to cope amid if the home side make a similar start to the match.

While their own stadium, Borussia-Park, can hold approximately 55,000 and generate quite a din when full, Andre Schubert's side have won just four matches away from home in all competitions in more than a year under the manager. They sit ninth in the Bundesliga table after missing two penalties in an uninspiring goalless draw against Hamburg on Saturday.

"Who are the favourites for this game?" said Thom. "That is difficult. I am German, so I must keep my fingers crossed more for the German team but I still have good memories of my time at Celtic.

"Moenchengladbach are quite a young team," he added. "Maybe they play better at home than they do away but I think it is going to be a tough game. It is difficult for me to say whether they will be able to cope with the atmosphere. We have stadiums here in Germany which are the same as in Scotland, real football stadiums where the atmosphere is very, very good. I am not sure where the crowd is more hostile but if Moenchengladbach's stadium is full it has 55,000, 60,000. It is a real football stadium and the atmosphere is great.

"What else can I tell you?" he added. "They are the kind of team who always like to play football, with a lot of quick passing. Maybe they haven't had the best results for the past four weeks or so but they are always good enough to play very, very good football.

"I don't really want to talk about individual names, but they are quite a compact team defensively. Christoph Kramer went back to 'Gladbach from Leverkusen, and he is a German international player. They have a lot of international players, not just German ones. Of course Manchester City and Barcelona are the favourites in this group but you never know how it will go. In my opinion this is a 50/50 match. I don't want to offer a prediction."

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The striker in Thom could hardly fail to be impressed by the man whose performance against Manchester City had scouts all over Europe talking. At the age of just 20, Moussa Dembele, plucked from Fulham for a cut price £400,000, gave the City defence a torrid time three weeks ago. As a youth coach, what excites Thom most is how much improvement there could still be to come. "He is still a young player and can still improve a lot," said the 51-year-old. "I hope he can keep away from bad injuries and illness but he looks like a really good player."

Aside from a three-match stint as caretaker following the departure of Huub Stevens, Thom's commitment to Hertha's youth team, rather than pursing a career in first-team coaching, is just one illustration of how efficiently German football churn out such an enviable conveyor belt of talent. "Me? I am happy with my job in the academy," he said. "Our job is simply to improve players and maybe in a few years we can see one of these players in the Hertha first team."

"It is not my job to answer why German teams usually do well against Scottish teams. But they do good jobs everywhere in the academies now. You never know what is going to happen in maybe one, three,or five years, maybe it will change, but I think the youth development in Germany is at a very high level."

Thom was a classy player who contributed more than just his 14 goals in 70-odd appearances for the club. He won a League Cup winners' medal in 1997 and received a league winners prize for the role he played in ending Rangers' run at ten league titles in a row in 1997-98, even though he made just 15 appearances for Wim Jansen's side before his mid-season departure to Hertha Berlin.

The 51-year-old hasn't returned to Scotland since 2008, but he keeps in contact with Pierre van Hooijdonk and still speaks warmly of the inspiration provided by the late Tommy Burns. "Of course Tommy was, what in Scotland you call 'the gaffer'," said Thom. "He looked after me during that time and of course he had a big influence. I have some stories but nothing I can tell you that is repeatable!

"I left Celtic in January 1998, and that was the year that Celtic won the league," he added. "I got a medal that year, but it is normal that sometimes you change club in mid-season. I was 32 years old then and it was difficult for me to play so I decided to go back to Germany.. It was the right decision for me but I still have very good memories of my time in Glasgow.

"I think all the Celtic supporters would say that their best memory of me was when we drew 3-3 at Ibrox. I scored the first goal that day and I think that was the best goal I ever scored for Celtic."