Although they had never been relegated in 1978, and had won the old Cup Winners' Cup a year earlier, Hamburger SV in 1977 were a team punching below their weight when former Borussia Mönchengladbach star Günther Netzer arrived on the Elbe.

As the story goes, the former West Germany midfielder was out of work having hung up his boots and was just hoping to help publish Hamburg's matchday program. However, then-club President Paul Benthien was so impressed by the 34-year-old Netzer, who had no previous experience in management, that he urged him to set his sights higher, and hired him as HSV's general manager.

Key roster changes and a new coach

As Uli Hesse relates his 2002 book Tor! The Story of German Football, Netzer found a team riddled with dressing-room infighting. He set about correcting the problem that same summer, firing coach Ozcan Arkoc and replacing him with Branko Zebec.

Netzer also quickly reached the conclusion that three of the players had been causing more trouble than they were worth and sent them packing. At the same time, he signed three second-division players who would go on be key parts of Hamburg's resurgence, Jimmy Hartwig (1860 Munich), striker Horst Hrubesch (Rot-Weiss Essen), and Bernd Wehmeyer (Hannover).

'Ridiculously tough' training sessions

Upon his arrival, Zebec changed the work ethic at the club. The Zagreb native, who had won the double of Bundesliga and German Cup with Bayern Munich in 1969, had a reputation of driving his players extremely hard in training.

England star Kevin Keegan, who was at the club from 1977 to 1980, welcomed the fact that Zebec had brought some much-needed discipline to a team that had been running roughshod over Ocan, but the Yugoslavian's methods took some getting used to.

England star Kevin Keegan during his spell with Hamburg

"Sometimes though, I felt his training regimen was ridiculously tough... I have never trained as hard. I was so tired when I returned home from training that I would go straight to my bed," he wrote in the 1997 book Kevin Keegan: My Autobiography.

Zebec's new training regime worked, with Hamburg, a team that had finished mid-table in 1978, winning the Bundesliga a year later, their first league title in 19 years.

Netzer finally gets his man

However, Zebec's problems with alcohol were an open secret, even if the local press at the time conspired to try to keep things quiet. In December 1980, though, Netzer decided things had gone too far and sacked Zebec, replacing him with his assistant, fellow Yugoslavian Alexandar Ristic on a caretaker basis.

Ristic led HSV to a second-place finish in 1980-81, but that wasn't good enough to convince Netzer to let him stay on as head coach on a more permanent basis, as the GM had long had his eyes on somebody else. In fact, that summer was the second time he would go after Ernst Happel; the first time had been three years earlier, when he wound up hiring Zebec.

But the 1979 Bundesliga title was no fluke, and despite his problems with alcohol, Zebec had very much turned things around at the club, as Felix Magath would remember in May 2019 in a post on his Facebook page, commemorating what would have been his former coach's 90th birthday.

"Branko Zebec was a very successful coach who formed a great HSV team," Magath, who went on to coach Wolfsburg to the Bundesliga title in 2009 and Bayern to two earlier wins, wrote. "I will always be thankful to Branko Zebec, because he led HSV and us players into a successful era."

Felix Magath was a key figure in the European Cup win

Happel, though, took the foundation that his predecessor had laid and took things a step further. Under Happel, Hamburg would win back-to-back Bundesliga titles and go on an unbeaten streak of 36 matches between January 1982 and January 1983.

They even made the final of the UEFA Cup (essentially the predecessor to the Europa League) in 1982, but were upset 4-0 on aggregate by an IFK Gothenburg led by a young coach by the name of Sven-Goran Eriksson.

But winning the Bundesliga again qualified HSV for Europe's premier club competition the following season, the European Cup (the predecessor to the Champions League).

Their campaign began with an all-German affair, as Hamburg faced the champions from the communist East, BFC Dynamo Berlin, in mid-September. After the two sides had played to a 1-1 draw in East Berlin, HSV advanced with a 2-0 win at home in the Volksparkstadion. The West Germans then went on to beat Olympiacos, Dinamo Kiev and Real Sociedad on their way to the final in Athens.

Odds stacked against them

So the stage was set for HSV to pull off one of the great upsets in a European Cup final.

While Hamburg had two players in their side, Hrubesch and Manni Kalz, who had lost in the World Cup final a year earlier (plus Magath, who was on the bench in 1982), Juventus had a truly star-studded lineup, featuring a total of six from Italy's 1982 World Cup-winning team, including goalkeeping legend Dino Zoff and the winner of the golden boot, Paolo Rossi. That's not to mention "foreign" World Cup stars Michel Platini of France and Poland's Zbigniew Boniek.

Also stacked against the West Germans was the atmosphere on a warm night in May 1983 at the Olympic Stadium in Athens, where Juventus supporters had the clear edge in terms of numbers and noise.

However, Happel knew a thing or two about how to beat Italian teams of the day. As coach of Feyenoord in 1970 he had beaten AC Milan on the way to winning the European Cup and in 1976, while in charge of FC Bruges, he'd knocked out Roma, before sending Juventus packing two years later. As coach of the Dutch national team, he had also beaten Italy on the way to the World Cup final in Buenos Aires in 1978.

Ernst Happel masterminded the win

To the surprise of many, Happel's men took the game to the Italian champions from the opening whistle, and Juventus just couldn't seem to get it into gear. It took just eight minutes for Hamburg to get the breakthrough they were looking for.

Perhaps with something to prove after having been left on the bench by West German coach Jupp Derwall in Madrid a year earlier, Magath, would be the hero of this night. Playing on the left of central midfield, he took a pass from Jürgen Grohe, his partner on the right, and approached Zoff's area. Recognizing what Magath was contemplating, grey-haired Roberto Bettega, playing in his last match before leaving for Canada to join NASL outfit Toronto Blizzard, jumped to block a shot that didn't come. Magath then strolled past him and after a step or two he really did let it rip – a screamer from just outside the box and into the top corner to a surprised Zoff's left. A few minutes later Kalz was unlucky not to make it 2-0, and Magath could easily have had another himself, later in the match.

The 1-0 final scoreline may make it sound like a boring game, but it wasn't. Giovani Trappatoni's side really started to try to go at Hamburg at the start of the second half, but Rossi, the man who had won the golden boot in Spain a year earlier, was ineffective, suffering not just from a paucity of service, but also getting caught offside on more than one occasion. In fact, Trappatoni so disliked what he saw, that he subbed off the star striker 11 minutes into the second period.

The Italians would have a late penalty shout denied, and while HSV goalkeeper Uli Stein, who would make his West Germany debut just weeks later, was forced into a few sharp saves, it simply wasn't to be for Juventus on this night in Athens. With the final whistle, Hamburger SV had absorbed everything the Italians threw at them.

After six years of English domination, in which Liverpool had won three European Cups to go along with two for Nottingham Forest and the last going to Aston Villa, the title was coming back to Germany. Hamburg were the new kings of Europe.