We talk a lot about shapes in football, don’t we?

How many times have you heard football commentators or pundits say that a match is ‘shaping up to be a classic’ or ‘they’ve lost their shape’? Paul Merson usually goes one step further and suggests something like ‘they’re running rings round them, Jeff’ before the hapless captives break out of the circle and, incredibly, score a goal and win the match.

Arsène Wenger relies on shapes a lot and, after their semi-final win over Manchester City, he reverted to his preferred back five letters forming this tried and trusted word, “You know I feel the club is in a very strong shape.”

When I heard that Arsenal were trying a relatively untried and certainly untested back three, I began to wonder whether Wenger was relying on triangles – the strongest shape you can get, even if most of us can’t spell ‘isosceles’ – as his preferred new shape. Certainly, nothing else had seemed to work and, to be fair to City (though they followed the Blackburn Rovers of buying success, they did not become headless chickens) Arsenal looked utterly shapeless in the first half of the first half.

Arsenal not only looked shapeless, they looked rather like a jelly or a plate of semolina that has been left out in the sun for much too long. They were pulled all over the place and star players like Oxlade-Chamberlain were out of position the moment they left the Wembley tunnel. Arsène’s tactical diagram in the changing room must have resembled the stars in a universe yet to be fully mapped – or a very big black hole.

The turning point in the game came when central defender, Gabriel, either received a helpful message from the other football angels in Heaven or a ferocious ‘I am going to have your balls on a plate’ glare from Steve Bould, who wasn’t technically talking about the perfectly spherical football that his hapless pupil appeared to keep running away from.

Suddenly Gabriel remembered that a) some Brazilians aren’t terrible at defending and b) Sergio Agüero comes from their historic, economic, geographical and politically most hated enemy territory.

For Spurs’ part, Arsenal did to City what Chelsea had done to the Faint Hart Laners just the day before. They allowed City to dominate the game and have all the play – Arsène must have been hypnotised by a club doctor from the French Antilles in agreeing to go through with this – before winning the game with practically their only two efforts on target.

One of these goals came from the only player who remembers that the goal is rectangular with a load of netting behind it, which gives it a 3D shape where the video cameras are sometimes hidden and sometimes work: Alexis Sanchez.

Some people have accused Sanchez of mischief-making this season in a play to get a move away from the Emirates. Other large financial assets such as Mesut Özil continue to depreciate at an alarming rate in a play to go back to somewhere sunny like Madrid where they didn’t have to play or move very much at all.

“People questioned us,” Wenger chirruped with glee at the end, as though he had come up with long-term solutions to the meaning of life and, well, the universe. “You can be divided or united and we have shown the right response.”

He might have inferred that they have stuck by the Arsenal name, rather than City, United, Rovers, Athletic, Wanderers, etc in order to show that they can still win football matches by sticking to their principles.

However, just as they dropped the words Woolwich and Royal from the Arsenal name as they left their homeland and the pub dressing rooms that had been part of the inspiration, sweat and brutality of their distant ancestors, so the six-letter words he used – ‘strong’ and ‘united’ – seem less apt than another: ‘hollow’ which means, literally, ‘a hole or depression in something.’