THE bowels of the Volksparkstadion's away dressing room are rumbling. Overhead an expectant throng of Hamburg supporters flick effortlessly through the greatest hits. High in one of the home stands, supporters packed in like marbles in a box give Home Sweet Home – the Hamburg fan anthem – an airing. There's an official Bundesliga banner that reads 'Relegation 2022' affixed to an awning to signify the importance of this match. But only one team present here can drop into 2.Bundesliga from German football's top flight and that side is Hertha Berlin, the visitors.

Down below, Mark Fotheringham is addressing the Hertha players. This is no callow collection of kids and journeymen. Gathered here are a body of international footballers, others who were previously bright young things and some household names nearing the end of their careers. Entrusted with training them, scouting today's opposition and working out how to beat them is the 38-year-old Scotsman, formerly a player with Celtic, Norwich City, Fulham and Anorthosis Famagusta and now a blossoming coach with successful stints at Karlsruher and Ingolstadt on his cv but a rookie at this level. He's addressing each man individually, cajoling them, exhorting each to reach their fullest potential – and telling them that none of the Hamburg players can hold a candle to them.

First up is former Celtic defender Dedryck Boyata. 'Boyata, you're a Belgian international, I wouldn't change you for Schonlau,' he says to the centre-back, before moving on to the next man. '[Kevin-Prince] Boateng, you've won the Serie A, you've played in England, I wouldn't change you for Sonny Kittel.' On he goes working down the line. 'Ascacibar, I wouldn't change you for Meffert, no way, you're an Argentinian boy who could play for the national team. [Marc-Oliver] Kempf, there's no centre-back in Germany that's got a left foot like you that's as aggressive as you. Platt [Marvin Plattenhardt], you're a player that can cause danger all over the pitch from set-plays, you've got an unbelievable left foot and you're a dynamic player. I'd never change you for their left back. Never in my life. It is impossible for us to lose this game. Impossible.'

Some 90-plus minutes later Fotheringham is proved right. Trailing 1-0 from the first leg, Hertha Berlin score after just four minutes. It's Boyata jumping highest to flick home an inswinging corner by Plattenhardt, he of the 'unbelievable left foot'. Three minutes past the hour, Hertha add the second, a goal that ultimately ensures their safety and again it is delivered via the boot of Plattenhardt, but this time there is no touch and his inswinging free-kick from the right bounces in.

Magath and Fotheringham are caught on camera embracing warmly at the final whistle, smiles spread wide across their faces. It is another feather in Magath's cap as a manager but there is little doubt about how much of a key role his lieutenant has played in this achievement or the importance of that pre-match pep talk.

“I stood over them and I said it to every single one of them and told them to their faces,” says Fotheringham, three weeks removed from the moment. “You could see the focus they had. They celebrated the game like they had won a World Cup final but I had to show to Felix Magath that I was ice cold and that I am not a guy to celebrate staying in a league. That was a side that should be challenging for the Champions League places. To me, personally, I know what it is to celebrate getting promoted with Ingolstadt, that's the kind of thing to celebrate. At Celtic I was brought up to win every week. It's normal.”

Hertha had been written off as 'no hopers' by the German media, “dead” as Fotheringham describes it. But the Scot and Magath, the former West Germany and Bayern Munich midfielder who steered Wolfsburg to the Bundesliga in 2009, performed a resurrection. Fotheringham had been at home in Angus when he got the call from his former manager at Fulham.

“Felix called me and said 'are you ready to come? I'm in talks with Hertha Berlin. I really want you by my side'. So I flew out to Berlin and met [sporting director] Fredi Bobic. He built the whole project at Eintracht Frankfurt. He's definitely someone who will work at Liverpool, Chelsea, Arsenal or Real Madrid [one day] – he's the best in the world. He's a first-class person and as a football guy he has got so much experience and he is very savvy in terms of the business.”

The remit from Bobic was simple: maintain Hertha's place in the top flight. There was an early complication, though. Magath, who turns 69 next month, had no sooner taken up the position than he was struck down with Covid. That plunged Fotheringham straight into the deep end for the pair's first match in charge of Hertha – he did not sink. The Berliners swept Hoffenheim aside, winning 3-0. Magath was quick to credit his young apprentice saying: “Most of the work was done by my assistant Mark Fotheringham, on the bench, in training, in conversations with the players. The key was clearly that Mark succeeded in conveying to the players, in training, the importance of remaining compact.”

Two further wins and a draw followed over the remaining six league matches. In the games they lost they remained true to Fotheringham's mantra of keeping it tight and their opponents close. Only in the derby against Union Berlin – in which they were thumped – did Hertha lose a game by more than a single goal.

No stranger to a strong work ethic, Fotheringham has the same appetite for graft as a coach as he did a player. He consumed eight Hertha matches on video in one sitting and by the time he arrived at their Schenckendorffplatz training ground he knew not only the names of every player but also their nicknames.

“The players were in shock. They were saying 'How does this guy know me? How can he speak German?'”

His homework gave him a flavour of what he had at his disposal. It became clear to him pretty quickly that in Plattenhardt he had a player whose dead-ball delivery was going to be a powerful weapon.

“I have never seen a left-foot like it. I had been involved with a team like Celtic and been to a UEFA Cup final and this guy's left foot was incredible. It was even better than Alan Thompson's - so I utilised the set-plays. It's a boring thing to train but I had to explain to the players that this could be a way to win games. I knew what the team was good at and I focused on the strengths. They had been working on a lot of ball possession without actually getting anything from it and causing themselves problems so I had to minimise the risk. I had to take a bit of the ball possession away and focus on being compact.”

Fotheringham calls the situation facing the side as they headed into the final weeks of the season a “match ball”. It's a term they use in Germany, borrowed from tennis, to underline the magnitude of a situation. Hertha passed up three 'match balls' which would have made them safe during the run-in: the first came at Arminia Bielefeld but ended in a 1-1 draw; the second at home to Mainz when Hertha chucked away a point with nine minutes remaining and the third slipped through their grasp in Dortmund when a 1-0 lead vanished in 16 second-half minutes and resulted in a 2-1 defeat.

That flung Hertha into the do-or-die decider with Hamburg.

“They thought in their heads that they were going to win,” he says. “But I know from previous play-offs with Karlruher and Ingolstadt that you have to have a level of humility. It doesn't matter what you do in the first game, it's about the second game.”

And so it proved. Fotheringham is now back in Scotland following the expiration of his contract. He says he will take a short break and see what options are but he has already had interest concerning a return to the Bundesliga where his name is being spoken about enthusiastically in the media. He is eternally grateful to Bobic and Magath for giving him his chance in the German top-flight but now he is determined to carve out a name for himself in his own right.

“The more it goes on the more I know I'm ready to be a manager. I told everyone seven years ago that I was going to work in the Bundesliga and I am the kind of guy that when I say I'm going to do something, I do it. I told my mum and dad when I was a wee boy that I was going to play for Celtic and I played for Celtic. I told people I was going to manage in the Bundesliga and I have done it. I want to be successful in football and I'm going to do it my way.”