Pierre-Emerick Aubameyang scored twice for Arsenal at a luminously empty Wembley Stadium as Arsenal withstood massed Manchester City pressure to seal a place in the FA Cup final. This was a frustrating night in north London for Pep Guardiola. Not only did City lose an FA Cup tie for the first time since February 2018, they lost in a way Guardiola teams sometimes do, choking on their own increasingly sluggish possession and passing themselves to death against opponents ready to sit deep.

For Arsenal this might just feel like confirmation of something. For the second time in four days Mikel Arteta’s team produced a performance of real defensive discipline against one of the Premier League’s reigning powers, not just absorbing pressure but breaking with great incision. Granit Xhaka was a calm, efficient presence in midfield. Nicolas Pépé used his speed advisedly, stretching City on the right flank, where Ainsley Maitland-Niles fought tigerishly and used the ball well. There are signs here of something starting to stir.

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At kick-off Wembley had been a mournful kind of place, the excitable tones of the stadium PA bouncing around the vast swooping stands. This is a gloomy concrete sepulchre at the best of times; and these are not, by any measure, the best of times. For FA Cup semi-final day the wide grey concourses were a ghost town, sweet trolleys and hotdog stands shuttered, a reminder of the havoc the current crisis has wreaked on FA finances.

Guardiola picked a starting XI crammed with ball players, with lIkay Gündogan the only real defensive presence in the front six. It was a team that seemed geared towards something similar to the Liverpool game at the Emirates in midweek, where David Luiz – yes, that David Luiz – had led the most stirring deep defensive performance of this late section of the season.

Here Arteta began with a back five as City produced an early swarm of possession, forcing the red shirts back towards their own goal, and almost into it at times. But it was Arsenal who had the first clear chance with 15 minutes gone.

David Luiz pulled a poor Aymeric Laporte clearance out of the air and played a simple straight pass through the centre of City’s midfield to Aubameyang, unmarked in front of goal. He shot powerfully, but straight at Ederson. It felt like an ominous miss – but not to Aubameyang, who opened the scoring four minutes later at the end of another move that met zero resistance from the sky blue shirts. Héctor Bellerín fed Pépé on the right. His deep cross curved across the City defence unimpeded and was met by a wonderful angled close-range finish from the skipper.

Arsenal continued to alternate deep defence with moments of counterattack. City still had the most of the ball, but there were hasty clearances, too, and some muddled passing. Shkodran Mustafi drew a flying save from Ederson, heading a corner back towards goal. And City still hadn’t managed a shot on target as the half-time whistle blew.

They were back out early after the break, beginning with a familiar urgency. For a while it was more of the same, just to an even greater degree: more sky blue passing patterns, more deep red-shirted defence. David Silva sparked one little interchange that saw Raheem Sterling shoot wide with a clear sight of goal. It took Arsenal eight minutes to construct a move in the opposition half.

Steadily, though, City seemed to run out of snap and fizz. It is some time since Kevin De Bruyne looked this clunky on the ball. With an hour gone the best midfielder in the Premier League had completed just 66% of his passes.

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He still almost provided the equaliser, dipping a free-kick over the wall and into the side-netting. Moments later Sterling fell under a challenge from Mustafi in the area but Arsenal survived the VAR check. Sterling then produced a horrible miss in front of goal. Surprised by the flight of a corner from the left, he could only deflect the ball weakly off his nose when any kind of header looked a certain goal.

It was Arsenal who emerged from behind their guard to score the second, killer goal on 71 minutes. The goal was made by a wonderful diagonal ball by Kieran Tierney, who curled an instant pass behind City’s high defensive line from the left side. Once again the finish was high craft. Aubameyang eased clear of Eric García, shifted his hips to change the angle, and slipped the ball through Ederson’s legs to make it 2-0.

City still pressed. Laporte crashed a shot on to the outside of a post. It never really looked like being enough. The final, two weeks from now, will provide a gloss on a strange and traumatic season.

The last week has also offered something else, a sense of the strings being tightened; and of a make-do-and-mend team responding, for the first time in some time, to a new set of rhythms.