If Manchester United were on top of the world, it didn’t last very long.

In 1999, Alex Ferguson’s treble-winning side was already so secure in its dominance of English football, that the new challenge of Arsene Wenger’s Arsenal seemed less of a threat and more of a welcome injection of competition for a team who had won five of the last seven titles. Still, the Gunners were brushed aside with ease, and by the end of January United’s only focus was the Champions League.

Not that they needed much concentration to win Premier League games, though. Ferguson’s side finished the season on an 11-game winning streak, and lost only three games all season, and although United travelled to Brazil to compete in the Club World Championship in January, that only freed up space later in the year as they didn’t take part in the FA Cup.

But that decision was significant for other reasons, too.

After conquering Europe, their request to compete in this new competition in Brazil rather than the oldest domestic cup competition in the world signalled that United were looking firmly towards global dominance of the modern world. Clearly Ferguson felt that he had cracked the Champions League, and his club weren’t content with just being the best team in England any more. They had thoughts on bigger things.

It wasn’t a ridiculous idea. Over the previous decade, the inception of the Champions League had created a new climate in the top European competition, and the last team to retain the trophy were the AC Milan side who won in 1989 and 1990 – winning the first of those two titles exactly ten years before United won their treble. Becoming the first side to dominate European football in this new, commercialised era would have been akin to unearthing the holy grail: the trouble was, United weren’t the only team looking.

April 2000 saw the Champions League reach the quarter-final stage, and after the turn of the century curiosity of the second group stage, United were drawn with Real Madrid, as the last two champions faced off. Both teams had competed – and failed – in the Club World Championship that year without actually meeting each other, but both had eyes on bigger goals.

Both clubs, too, were in a strikingly similar historical state. Both won the competition in the late 90s, having both won previously in the late 60s. They had waited generations to lift the trophy again, and together they were probably the best teams in European football at the turn of the millennium. So when they met in the Champions League, it wasn’t just a tie for a semi-final spot, it was a battle for supremacy.

But if the two clubs’ historical context was linked, the state of their league campaigns wasn’t. Whilst United went into the first leg having lost only one league game since October 30th, Madrid had won only once in five league matches. And whereas United would go on to win the Premier League title by 18 points, Madrid would finish fifth, behind Real Zaragoza.

That form on the homefront even looked to be transposed into European competition after the first leg, too, as United went to the Bernabeu and came away with a 0-0 draw. But the second leg didn’t just define the tie. It defined a new era of European football.

For one thing, it’s a game where Alex Ferguson appeared to have been beaten at his own game. If United wanted to be the heirs to Arrigo Sacchi’s Milan side of ‘89 and ‘90, they certainly didn’t share the same worldview as the Italians. Milan were a compact side who built their foundations on a solid defence. United, meanwhile, were attacking and courageous, outscoring their opposition, not under-conceding them.

United knew a win would guarantee them a place in the semi-final, and so setting out to attack the Spanish team was always going to be the aim, and although they were unlucky in the game – a Roy Keane own goal put them behind in the first half – United were felled with the very sword they lived by, losing 3-2 and crashing out of the competition. It was a loss which precipitated a rethink from Ferguson in later years, leading to a more circumspect approach in big games as well as Darren Fletcher and Ji-Sung Park.

“Since then United have been a different side in Europe and in big games domestically: whereas once they were swashbuckling and intrepid to the point of naivety, now they are worldly, cautious and always look under the sauce to see if it really is pasta.”

Rob Smyth, The Guardian, 2013

Few football games are as pivotal as this turned out to be, but even so, perhaps the most memorable part wasn’t what happened in the aftermath, nor was it even a goal, but a moment of genius during the game itself.

Having just scored a second goal to stun Old Trafford, Madrid were buoyant, and when Fernando Redondo found himself one-on-one with Henning Berg on his side’s left wing, his confidence was evident. They say that there is a fine line between confidence and arrogance, but when you’re 2-0 up at the home of the European champions and arguably the best team in the world, you won’t hear much argument.

It’s that heightened sense of possibility that inspired Redondo to beat Berg with an outrageous backheel which will be remembered forever. Footballing parlance is prone to exaggeration, but, as with supreme confidence, there’s a time and place for the cliches. To say that Redondo ended Berg’s career isn’t strictly true, but within five months, the Norwegian defender had returned to Blackburn Rovers on loan. He may have been spent at the top level anyway, but Redondo applied the coup de grâce.

Once past Berg, Redondo looked up and picked out Raul who was alone in the six-yard box. He tapped in the third goal, and whatever hopes United still harboured of a comeback, a place in the semi-final of the Champions League, and even world dominance, well, they were over.

Real Madrid would go on to win the title that season, and would win again in 2002, lifting three titles in five years. Their iconic white shirts, their huge stadium and their mass appeal already made them a force in a globalised footballing landscape, but their dominance made them unquestionably the biggest club in the world. It gave them a pulling power that no other club could boast. The excesses of the Galactico era after 2003 may not have extended their sporting success, but their victory over then-champions United in 2000 ensured that it was Madrid and not their Manchester rivals who got their hands on the treasure, consolidating their place not just at the top of Europe, but the top of the world.

United didn’t disappear off the face of the Earth, and they too would benefit from all the same trappings of football’s mega wealth. But despite their prestige, they wouldn’t win the competition again until 2008.

But perhaps the most telling illustration of the supremacy that Madrid gained because of their victory at Old Trafford in 2000 is the fact that eight years later, when Cristiano Ronaldo helped United to their next Champions League triumph and bagged himself the Ballon d’Or, he was snapped up by Madrid for a world record fee.

United aren’t paupers. Since the 1990s, they have been one of the biggest and richest football clubs in the world. But it’s hard not to look back at one Champions League tie in 2000 and wonder what would have happened had they beaten Madrid. Becoming the first club to retain the Champions League and taking a stranglehold over the Spanish giants at the start of the stunning financial boom in football could have made United into a team of Galacticos.

In 1999, United were at the top of the world, but it lasted only until Madrid regained the summit. And in terms of finance, power and prestige, it’s hard to argue that they haven’t been there ever since.

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