The most prominent banner inside the Allianz Arena felt like a measure of the new Bayern Munich. "Schöne heile Welt" it read. Translated, it means a beautiful, perfect kingdom. It's not the thing you would normally expect of a football crowd and yet somehow it felt so appropriate. Everything feels right about Bayern at the moment, and the sense that something truly special is coming together.

What happened to Barcelona on Tuesday, and the scrutiny that has followed, was encapsulated by the front cover of AS, the Spanish sports daily. "Fin de Ciclo," was the headline. Yet this did not feel like the end of an era. It felt like the beginning of a new one.

Bayern had inflicted the ordeal without Toni Kroos. Next season they will have Mario Götze from Borussia Dortmund, cherry-picking again from their Bundesliga rivals. This is into a midfield that already boasts the power, artistry and football intelligence of Thomas Müller, Bastian Schweinsteiger, Javi Martínez, Franck Ribéry and Arjen Robben. It is a daunting prospect, not just for the clubs who regularly compete in the Champions League but those who have become a speck in the distance in the Bundesliga. More than that, it is another jolting reminder for the Premier League, from Manchester United down, of the gap that has opened up at the top, and what a challenge it is going to be to close it.

Bayern, to recap, have a 20-point lead in Bundesliga, a plus-75 goal difference and were confirmed as the champions of Germany in the first week of April. At the point when other teams start citing fatigue, they seem to be getting stronger. Jupp Heynckes's side, the first to beat Barcelona 4-0 since Dynamo Kyiv in 1997, have scored 55 goals in their past 10 games. No team since the introduction of the away-goals rule has overcome a first-leg deficit of that score in European competition, in 171 attempts. If Bayern get one in the Camp Nou, Barcelona will need six. And who would bet against Bayern scoring? It is more than a year since the last occasion they did not manage an away goal.

Heynckes had planned for this moment with almost forensic detail. He talked about the hours he had spent watching footage of Barcelona, not just collectively but individually, man by man. "You have to analyse a team," he explained. "What is their playing style? Where do they move? How do they move? Where do they go? How do they play? I did that. I analysed them."

It was not a coincidence Dani Alves did not have the freedom to set off on those overlapping runs from the right of defence. The full-back had played more like a winger against Paris Saint-Germain. Heynckes knew they would have to pin him back. "I had a PowerPoint presentation with the players," he continued. "We didn't want to concede a goal. We knew we had to neutralise [Lionel] Messi. And we have a lot of creativity, quality and class when we are going forward. We create the space and we use it and we can beat any opponent playing that way."

Jordi Roura, the Barcelona coach, repeatedly made the point that Bayern had been "very physical". This can be meant as a complaint, or even a thinly veiled insult, but Roura said it ungrudgingly. The team at the top of La Liga looked weary in comparison and that, more than anything, is perhaps the area Barcelona must address first. This is a side that operate with virtually no rotation policy, playing in their 51st game of the season, and from the 65th minute onwards they looked shot.

Gerard Piqué described it as a "thrashing". Barcelona, like a lot of serial champions, are never usually slow to pin the blame on the referee when decisions go against them. This time, despite genuine grievances, they knew it was futile. "Bayern were the better team, in everything," Messi said. "They were stronger, they scored from set pieces, every second ball was theirs."

The end-of-empire stuff still feels like a classic case of knee-jerking when they have spent so long redefining the art of how to out-pass opponents. A defeat this harrowing will compel Barcelona to rethink their strategy, or at least a part of it, but what happened in Munich was shocking, for the most part, because it was such a rarity. Their age range is good – only one player, Xavi Hernández, over 30 on Tuesday – and this is still a side with assorted glories in front of them if they add some variety to their play and are not arrogant enough to neglect their shortcomings, starting off with an acceptance that they need to work on defence. This is the first time since 2001 they have conceded 60-plus goals in a season. Even the most refined teams need to head the ball away from time to time.

Bayern tick every box. Heynckes has moulded a team with strength of personality, playing with structure, drive and creativity, the collective sense that they know exactly where they want to be and have the wit and gumption to do it. The 2-0 home defeat to Arsenal, after winning 3-0 in London, smacked of complacency and was perhaps the jolt they needed. Otherwise this is a team with absolutely no obvious weaknesses. Their oldest player on Tuesday was Ribéry, two weeks after turning 30. Müller is 23; Javi Martínez, 24; David Alaba, 20. Kroos is 23 and Götze 20. This is a team, as Gary Neville observed in his television duties, that "is ready to win". Neville did not just mean once, he meant serial winning. "Sometimes you just have to congratulate the opposition," Alves said. "And Bayern are the best team we have played for a long time."