For 20 minutes in 2010 Arsenal must have felt as if the pitch at the Emirates Stadium had been tipped towards their goal. The ball just kept coming back and on the rare occasions when they got it, they were staring up a mountain. Barcelona were having fun at their expense, Pep Guardiola's side so dominant that the home fans could only watch in stunned silence. Few Champions League quarter-finals have been so one-sided. Manuel Almunia's defiance kept Barcelona at bay for a while but they led 2-0 by the hour thanks to two Zlatan Ibrahimovic goals. The final score? Two-all.
Arsenal went one better when Barcelona and Guardiola returned a year later in the last 16. Again Barcelona were unable to make their superiority count, taking the lead through David Villa but losing 2-1 after conceding two late goals. Barcelona were cruising until Guardiola replaced Villa with Seydou Keita in the second half, a substitution for the sake of making one, and handed the initiative back to Arsenal.
The relevance of those encounters might seem questionable now, especially as Barcelona won both ties after the second leg at Camp Nou. But tonight Guardiola is back at the Emirates, this time with Bayern Munich. The German club are expected to win handsomely and to go on to become the first team to win the Champions League in successive seasons. It is hard to see Arsenal standing in their way – but at least they can be encouraged by their home record against Guardiola.
"I have never won here," the Spaniard said. "I learned that you can never dominate Arsenal for 90 minutes. You can dominate for 30 minutes, to half-time, for 75 minutes, but for 90 minutes it is impossible. Arsenal, with these quality players, you always have a problem."
Guardiola got the better of Arsène Wenger in the end. Yet if there was one chink in the armour of his Barcelona, it was in their occasional habit of sailing unnecessarily close to the wind. It was too easy at times, as if they grew bored and kept their opponents hanging by a thread to create the illusion of a fair fight.
Mostly they emerged unscathed, even though Arsenal would have beaten them with 10 men in 2011 if a late chance had fallen to a more refined striker than Nicklas Bendtner. But it has not always worked out. The scars of Barcelona's farcical semi-final defeat against Chelsea in 2012 will endure for a long time.
Bayern are also not immune to complacency. Their sheer remorselessness over the past two seasons, first under Jupp Heynckes and then Guardiola, makes them a formidable proposition and, if everything plays out as expected, they will dispense with Arsenal comfortably. Yet Arsenal will remember the scare they gave Bayern at this stage last year.
The tie looked over after Bayern won the first leg 3-1 at the Emirates but the German club went through only on away goals after losing 2-0 at the Allianz Arena, although the thrashings of Juventus and Barcelona in the subsequent rounds suggested that the loss of focus against Arsenal was just a blip.
So Arsenal, who have made vast strides in the past year, are not entirely without hope and Guardiola clearly does not share José Mourinho's view of Wenger as a "specialist in failure".
"Life is not only trophies," Guardiola said. "Arsenal compete with huge teams. I have a lot of respect for Arsène. He always likes good players, always plays in a good style." Arjen Robben smiled when the subject was broached. "I have heard some people already discussing this," the winger said.
Yet Arsenal know any analysis that picks holes in Bayern and Guardiola is a pointless exercise, like going to the world's best steak restaurant and complaining about the vegetables. Bayern won a treble last year, have power and skill in equal measure, possess unrivalled strength in depth and are 16 points clear at the top of the Bundesliga. They have lost twice in all competitions this season.
Regular watchers say that Bayern have become even better since Guardiola replaced Heynckes last summer, improving on perfection by hiring a perfectionist. "We had to be focused from the first day with a new coach," Robben said.
Some have attributed Guardiola's success at Barcelona to the quality of players at his disposal, yet they were on the floor when he was appointed in 2008. It was Guardiola's first job in management. He could have fooled us.
Barcelona won La Liga three times and the European Cup twice in four years. Guardiola turned them into the greatest side in history. They could not have done it without him.
Battling with José Mourinho at Real Madrid took its toll, though, and Guardiola looked exhausted when he left Spain two years ago. But a year in New York recharged the now 43-year-old's batteries and Bayern became the envy of the rest of Europe when he chose them. Guardiola's style of football – always entertaining, never dull – makes him the most coveted manager in the world.
What other manager would have turned Philipp Lahm from a world-class full-back into a holding midfielder of considerable poise? Guardiola called the German the most intelligent player he has ever worked with. "It would be impossible to be here without him," he said.
Guardiola has also played without a striker, often using Mario Götze as a false No9, and there has inevitably been a greater emphasis on dominating possession in midfield with the short, snappy passing triangles that defined Barcelona. He said his side would control Mesut Özil – "a big talent" – by depriving him of the ball.
Yet Bayern are far more physical than Barcelona and have been direct at times under Guardiola, who said he came to Germany to prove he could succeed in another league. His squad provides him with so many options that there is always a solution in awkward situations. Weaknesses, like a needle in a haystack, are there to be found – but what if the needle keeps moving?
Arsenal will have to squint hard – and then, if Bayern's boot is hovering above their throat, close their eyes and pray that they miss.