It took Bayern Munich just 107 seconds to breach a Benfica defence that had been described as “perhaps the best back four in Europe” by Pep Guardiola beforehand. But far from opening the floodgates, a match that opened with cheers ultimately ended in groans as the home side failed to capitalise on that early breakthrough ahead of a nightmare-inducing return to Portugal.

The Bavarians exacted their usual measure of control on the match, dominating possession and swarming Benfica on the rare occasions they had the ball. Guardiola’s side stretched the play in the early exchanges, making the pitch as wide as possible and overloading the flanks. Fresh from his winner at the weekend, Franck Ribery was a menace down the left wing early on.

Perhaps unsurprisingly, it was a left-wing cross from the adventurous Juan Bernat, marauding beyond the Frenchman, who unlocked a Benfica defence that were given no time to settle into the occasion. At that point, after just two minutes, the Portuguese side’s hopes of making a first semi-final in 26 years looked like they would crumble away very quickly.

At this stage last season, Bayern put six goals past Porto on home turf after being stunned in the first leg – the suspicion was that Benfica would be lucky to escape without suffering a similar fate. But Bayern’s intensity dipped, their defensive concentration slipped, Benfica’s winger’s began tracking the overlapping runs of Bernat and Philipp Lahm and the back four that were so acclaimed beforehand grew into their task.

Benfica arrived at the Allianz Arena with a phenomenal defensive record, even if it took a while to show it. In the major leagues, only Atletico Madrid, Juventus, PSG and Bayern themselves have shipped fewer goals than the 19 Benfica have conceded in the Primeira Liga. And now Thomas Muller and Robert Lewandowski know exactly why Guardiola was so keen to talk up Benfica's defensive talent pre-match.

The strike duo, who have proven to be every bit as capable of sprinkling stardust on matches as the more lauded acronym attacks of Barcelona’s MSN and Real Madrid’s BBC, were almost entirely shut out of the game. Lewandowski had as many touches of the ball as goalkeeper Manuel Neuer, while Muller – substituted with the home side still pressing for a goal – had the worst passing accuracy of any Bayern player.

Though clearly on top throughout, Bayern lacked any real spark. Even the introduction of Kingsley Coman, who coruscated against Juventus, could not wake the Bavarians from their slumber. Late on and clean through, Lewandowski’s poorly weighted attempt to play an easy square pass to Lahm, rather than shoot, summed up a performance that never quite clicked in an attacking sense. Critics have suggested Guardiola is guilty of asking his team to over play, and rarely has that been more evident.

What will worry the Catalan coach most is how out of sync his attack is right now. Tuesday’s result marks Bayern’s third straight 1-0 win in all competitions, and, as at the weekend, the lack of goals from his strikeforce needed to be compensated by a midfielder – Muller has only scored in three of the 11 domestic matches Bayern have played in since the turn of the year.

It is the first time they have failed to hit more than four goals in a Champions League home match this season, such has been their dominance on home turf recently, and the first time since September 2014 that they have been limited to just one goal in a European tie at the Allianz Arena.

At the other end of the pitch, Benfica found holes in a defence that still has massive question marks over its ability to provide the necessary foundation for Champions League glory. The visitors may only have been afforded with 32 per cent possession, but twice Jonas was presented with clear-cut opportunities to net a precious away goal. Twice he fluffed his lines.

The veteran Brazilian may have 32 goals this season, but a more lethal striker would have punished Bayern – the stats will show that Neuer has collected three straight clean sheets, and made just three saves in 270 minutes, but he was lucky to escape with that record intact. To compound matters, Jonas picked up a yellow card that rules him out of the second leg, a moment that feels as decisive as the night’s solitary goal.

One positive for Guardiola will be the nice blend of creativity and aggression that Arturo Vidal and Thiago provide. The Chilean once again stepped up for his side, as he has been forced to do with increasing regularity, while the Spaniard’s probing passes ought to have yielded greater success.

Benfica teenager Renato Sanches, so regularly on the front pages in his homeland and continually linked with a mega-money move to Manchester United, did well to compete against such a tigerish midfield pivot. The 18-year-old looked classy and composed on such a grand stage, and if he can raise his game again at the Estadio da Luz, Benfica – even without Jonas – will be quietly confident of springing a surprise, much as Porto did.

Tuesday’s clash will not live long in the memory, nor will it immediately come to mind when looking back at Guardiola’s time at Bayern. But his 150th game neatly summed up the feint qualms fans of die Roten have harboured. For all their dominance and despite the win, they produced few chances of real note, looked edgy at the back and have left themselves with plenty to do to progress. Guardiola's farewell tour is still yet to really take off.