It seems astonishing now to think that it's only two years since Arsenal beat Barcelona 2-1 in the Champions League.
True, they were a little fortunate to survive a first-half pummelling in that game with the concession of only one goal and, true, they were comprehensively beaten 3-1 at Camp Nou in the second leg but still, Arsenal were closer to Barca in style than any other team in the world. On Tuesday night it became abundantly clear that Arsenal have ceded that position: Bayern Munich now stand as pretenders to Barcelona's crown and the truth is they are probably closer to them in ability than Arsenal ever were.
Over the past two seasons, in the top five leagues in Europe, only Barcelona have had more possession than Bayern, only Barcelona have had a better pass completion rate than Bayern. Bayern came late to pressing - even later than most of German football - but since Louis van Gaal's tenure they have begun to press as well. They don't squeeze with quite the intensity of Barcelona but the ethos is the same: win the ball back as high up the pitch as possible, try to catch opponents with rapid transitions and, if that doesn't work, fall back and rely on an attritional possession game. Five of the Bayern team that started against Arsenal were products of their academy: it's easy to see why Pep Guardiola, so used to the Barcelona way of doing things, would feel an affinity with the club.
It's not just in terms of style on the pitch that Bayern and Arsenal share a vision. Both have preached the value of sustainability against what Arsene Wenger has termed the "financial doping" of billionaire ownership. Again, though, it's hard to avoid the feeling that Bayern have surpassed Arsenal.
True, Arsenal make more each year in matchday revenue, £117.7m to £85.4m, and true they make more from television rights, £107.1m to £81.4m (an advantage that will increase next season as the new Premier League television deal kicks in) but in terms of commercial revenue , Bayern are streets ahead. They make £201.6m per year, the highest figure of any club anywhere in the world, as opposed to Arsenal's £64.9m. That is based on sponsorship and partnership deals with, among others, Adidas, Paulaner Brewery, Audi, Coca-Cola, Samsung, Siemens, Burger King, Continental and Sheraton. An existing partnership with Lufthansa was extended for another five years last week. Bayern is an institution, it is the establishment and it makes sense for major companies in Germany to align with it; you wonder how many of Arsenal's sponsors will remain loyal should they suffer a protracted downturn in form.
You wonder too how long Arsenal's ticket prices can remain as high as they are - or at least whether they can be increased further - if trophies remain elusive. Although tickets for Category C matches, against the supposedly least attractive opposition, start at £25.50, for Category A games prices range from £62 to £126. The average price of a ticket at Bayern, by contrast is £31.25. That's relatively expensive in Bundesliga terms and includes standing tickets - and it would certainly be misleading to portray Bayern as some sort of charitable concern - it does seem a healthier position in terms of long-term growth.
And then there is the matter of character. Arsenal are as flaky as ever, always prone to mistakes and moments of sloppiness. Bayern, by contrast, are impressively robust. Last season, losing in the Champions League final in their own stadium, having conceded a goal with two minutes remaining, having missed a penalty in extra-time, was a crushing blow, particularly as Bayern also finished second in the league and lost in the final of the German Cup. It would have been easy to imagine a gloom sinking over the club, or panic leading to the replacement of the coach.
But instead, Jupp Heynckes was given a further season, permitting a smooth transition to Pep Guardiola, even if Heynckes would have preferred an extra year. Again, it's easy to imagine a coach's authority being undermined by the knowledge that he would be leaving, but since Guardiola was confirmed as Bayern's new coach they have won five Bundesliga games in a row, scoring 13 without conceding. Far from showing signs of weakness, they have become the efficient machine of Teutonic cliché, overwhelming opponents remorselessly as though determined that Heynckes should leave in a deluge of trophies and records.
Yet the stereotype is as wrong now as it was in the seventies when Bayern practised a form of Total Football. This is a team that plays with a dash and a swagger that has been built steadily by the president, Uli Hoeness, and the chairman of the executive board, Karl-Heinz Rumenigge. The summer acquisitions were part of a coordinated plan: Javi Martinez gives tempo-setting steel at the back of the midfield; Dante is a centre-back who can pass; Xherdan Shaqiri reduces the reliance on Arjen Robben and Franck Ribery; Mario Mandzukic is a more complete forward than Mario Gomez and a player who can initiate pressing.
It's all part of a style set in place when Van Gaal succeeded Jurgen Klinsmann in the summer of 2009, one that coaches are expected to fulfil. Again, it's hard not to be struck by the contrast with Arsenal. As the possibility that Wenger's time may be drawing to a close at the Emirates is raised again, what's striking is the vacuum his departure would leave.
Bayern have made mistakes in the past, not least in the appointment of Klinsmann, but at the moment they seem the model of a well-run club. You only wonder whether Guardiola can really improve them.