“Die Bundesliga ist für uns vorbei.” Pep Guardiola’s infamous declaration in a 2014 press conference, with the title in the bag, that Bayern Munich’s league campaign was over might have been off the cuff, but he spent a long time afterwards trying to live it down. The drop in intensity that followed his words prefaced a pair of sluggish performances in the Champions League semi-finals against Real Madrid, and Guardiola would later openly admit his error. It was probably the biggest mistake of his enthralling three-year spell at the Allianz Arena.

Jupp Heynckes is not about to make the same mistake. Three days before the Champions League quarter-final first leg at Sevilla, the coach picked a devilishly attacking line-up to face Dortmund in Der Klassiker on Saturday evening. They swarmed over their opponents, supposedly their most dangerous domestic adversaries, like a pack of wolves left unfed for days.

Bayern led before the end of the fifth minute of the match, with Robert Lewandowski – inevitably – expertly sweeping in a pass from the outstanding Thomas Müller. Dortmund were reprieved when VAR ruled out a second by Franck Ribéry, still inside the first 10 minutes (curiously, Lewandowski’s marginal offside position for the opener went undetected), but still trailed 3-0 by the 23rd minute and left the pitch at the interval shell-shocked, after a quick one-two punch from Lewandowski and Ribéry made it five at the halfway point.

It all worked out perfectly for Bayern who, by refusing to take it easy in the first half, could do just that in the second before their trip to Andalucía. Heynckes was able to give a breather to David Alaba, the excellent James Rodríguez and Ribéry. Joshua Kimmich, whose importance was underlined in that he was a rare first-choice player awarded a rest, came on for the second half to whizz around Peter Stöger’s dispirited team, and he laid on Lewandowski’s hat-trick goal late on with an intrepid burst on the outside.

OK, maybe it didn’t work out quite perfectly. That would have involved Schalke dropping the points against Freiburg earlier in the afternoon which would have made the title mathematically certain for Bayern. Instead, the 2-0 win for Domenico Tedesco’s side, which strengthened their grip on second place at Dortmund’s expense, meant the kings must wait for the short trip to Augsburg on Saturday to be crowned.

That felt like a minor detail on a day when everything else went so well. Whether Heynckes will employ such an offensive line-up at the Ramón Sánchez Pizjuán is open to question, but one wonders how many teams could resist Bayern in this form. As well as Müller, Lewandowski and Ribéry (who bamboozled poor Lukasz Piszczek on the left), James suggested he could be the side’s creative fulcrum in the post-Ribéry and Robben era, with a goal and two assists from the left of a three-man midfield. Sporting director Hasan Salihamidzić was noncommittal when pressed by journalists on whether Bayern would take up the permanent option on the Colombian’s services at the end of next season but playing like this, it seems a formality. “He had,” wrote Süddeutsche Zeitung’s Benedikt Warmbrunn, “played passes with a fairy-light ease. He had accelerated the game and he had decelerated it, as suited the moment.”

Bayern’s Franck Ribéry, top, jumps over Dortmund goalkeeper Roman Bürki. Photograph: Matthias Schrader/AP

Presumed to be at risk after Carlo Ancelotti’s sacking, having been recruited as per the Italian’s wishes, James has excelled under Heynckes. The future is especially germane, with Karl-Heinz Rummenigge confirming after the game that Bayern aim to have Heynckes’s successor in place by the end of April.

On the other side this was humiliating for the visitors, and not only because of what happened on the pitch. The wretchedness of their plight even elicited sympathy from Bayern. “One can only hope Dortmund will be on track again next week,” said Müller after the game, “because we need good teams that represent us [the Bundesliga] well on the continent, not this year, but next year. It’s important that Borussia Dortmund find their way back to their old strength.”

Former BVB stalwart Mats Hummels went into the away dressing room to commiserate with his old team-mates afterwards, having offered them empathy in front of the media by recalling a dim, distant thrashing by Karlsruhe when in Bayern’s under-17s before, rather less helpfully, recalling his own part in a Dortmund thrashing at Bayern when still at Westfalen. The pats on the head underlined that the time when Dortmund were Bayern’s major competitors, or even major irritants, has been and gone.

In his own post-match summary, Stöger sounded like he was closing the door on any hopes of extending his tenure beyond the end of the season. “I’m happy and proud to be able to work here,” said the Austrian, “but my life is not defined by the fact that I’m on the touchline at BVB.” To say that a new coach – even Julian Nagelsmann – could push Dortmund back towards competitiveness is plainly not the case, though, and as sporting director Michael Zorc signed a new deal until 2021 this week, his acknowledgment that “new influences and ideas” are needed should preface a rebuild off the pitch as well as on it, where the squad has talent but looks increasingly uneven.

The first domino to be tapped is Matthias Sammer, who will return as a consultant. Reports suggest that Sammer’s role – his first since stepping down from Bayern in 2016 after illness – will be a fairly informal one, meeting the top brass every fortnight to give his opinion on the club’s direction, rather than getting involved in day-to-day operations, and he hasn’t signed a contract – at least for now. Another former stalwart, Sebastian Kehl, is being lined up too.

For now, one wonders how much longer Bayern and Dortmund’s meetings can be defined as Der Klassiker. Heynckes, as so often, cut to the quick while endorsing BVB’s recruitment of his former colleague Sammer as “in their current situation,” during his post-match press conference. That Bayern had no rivals in their march towards the title was already clear, and we should not be surprised that they reminded us of that in such brutal fashion.

Talking points

• Dortmund weren’t the only side to take a 6-0 hiding on Saturday. That fate also befell Cologne; having opened a pathway to a great escape before the international break, they slumped at a rampant Hoffenheim, who have half-an-eye on a Champions League place, being just four points adrift. Effzeh’s performance was “a joke,” said their infuriated goalkeeper Timo Horn, with hard-earned points for Mainz and Wolfsburg now leaving them six away from the relegation playoff spot.

• More chuckle-worthy was the manner of Werder Bremen’s winner against Eintracht Frankfurt, as the usually-excellent Lukas Hradecky let David Abraham’s back-header slip into his own net for an extraordinary own goal. That cost Eintracht, with Leipzig’s thrilling 3-2 win at Hannover letting them move into fourth.