In a campaign where everything is piling up and Arsenal have suffered a torrid last two months, the considered economist in Arsene Wenger still goes back to the little moments that could have gone a different way, and led to a different season. He particularly points to their last game against Manchester City, and the match just before it away to Everton. The latter brought Arsenal’s first league defeat in 15 since the opening day at home to Liverpool, and then another in quick succession.

“It is a strange season because it just looked it escaped from us in moments,” Wenger said. “Not for a lot, but every time for a fraction that was on the other side. That is why it is very difficult, because it started at Everton where we were 1-0 up. At City we were 1-0 up. And things went just against us and we could not respond. But as well it is a weird feeling.”

It is a slightly curious argument too. Far from being either-or sliding-door moments, the nature of how the problems have multiplied since suggests those games merely reflected what were then growing flaws within the team. Wenger’s ‘fractions’, after all, have added up. Arsenal haven’t really properly recovered since those December defeats, and it has infamously led to the worst run of results in the manager’s entire 20 years at the club, involving some hugely concerning implosions.

The wonder, too, is how Pep Guardiola feels about that point of view. City have not been consistent or all that convincing this campaign, but it cannot be denied that they regularly create an abundance of good chances, suggesting that there is something more there. There have also been many games - and particularly big games against Chelsea, Tottenham Hotspur and most recently Liverpool - where Guardiola has been left rightly lamenting how different the results and season could have been otherwise.

"That’s the way it is," he said again on Friday. "I remember in a lot of important games how we played. We have a lot of games where we have got to the bylines, and we have wingers for that in Leroy [Sane] and Raheem [Sterling] in the right area, but we were not able [to finish the chances]. What happened, I don’t like to say we were unlucky, no. We were not good enough. It is simple like that. We were not good enough in the boxes.

"That depends a lot on the opponents, or the referees. At the end of the day, I believe you can count the mistakes from everybody, from the opponents, from the referees, but always we concentrate on our mistakes. We can always improve on our mistakes. We cannot control the decisions of the referees, that happens everywhere, with all the teams around the world. We can improve what we can control.

Arsenal have the same season every year Show all 8 1 /8 Arsenal have the same season every year Arsenal have the same season every year Surprise early defeat A surprise early defeat, such as 2013/14's to Aston Villa or 2015/16's to West Ham United, makes July's Emirates Cup win seem like a distant memory. Getty Arsenal have the same season every year Impressive win against top club A promising win against a title rival, like last season's 3-0 victory over Manchester United or this season's win over Chelsea, has the Emirates hoping for the best again. Getty Arsenal have the same season every year Injuries start to mount up However, a long queue starts to form outside the treatment room. Key players, as well as regular absentees, tend to be the victims. Getty Arsenal have the same season every year November curse strikes again Arsene Wenger's side then begin to unravel in November, with the curse kicking in after an away defeat against one of the top flight's lesser lights. It's around now that the already-faint hopes of a title challenge start to fade. Getty Arsenal have the same season every year Champions League elimination The most predictable part of it all comes in February, with Champions League elimination, usually to Bayern Munich, Barcelona or Monaco, if they are really unlucky. Getty Arsenal have the same season every year Title hopes finally killed off A heavy, signature defeat to a fellow top six side puts paid to any lingering hopes of a title challenge in late February or March. 2013/14's 6-0 reverse at Chelsea, Arsene Wenger's 1,000th game in charge, is perhaps the most memorable example. Getty Arsenal have the same season every year Strong rally to finish The pressure is off, time to turn the style on. A rally at the tail end of the season does wonders for Arsenal's league standing, but little to combat allegations of flakiness. Getty Arsenal have the same season every year Top-four finish Arsene has his 'trophy'. Champions League football is coming to the Emirates again next year. What more could the fans want? Getty

"I remember against Chelsea, we were 1-0 up, and we had three or four opportunities in front of goal. In many, many games, it was like this, and we were not able to do that. We have specific qualities in our players to create those chances. We are unable to score goals and we are not solid, so the midfield players, the attacking midfield players, Yaya, Fernandinho, Silva, Kevin de Bruyne, the people to create are there. After that, we are not solid enough when we don’t score goals. That was the thing until now... in important games we need the whole squad to get all the goals we want."

All that has ensured there is a certain pressure on both teams ahead of Sunday’s meeting at the Emirates: City to win a league game for the first time in three and keep chances of a top-four finish in their own hands; Arsenal to win just a second league game in two months and regain control of a season that is fast unravelling.

Guardiola will be looking to arrest his side's recent run of poor results at the Emirates (Getty)

Those differences in perspective and objective also reflect a difference in how they approach the game, and why the onus is more on Wenger than Guardiola, beyond the obvious furore over the Arsenal manager’s future.

We know that City will broadly attack the game in their usual way, even if the Catalan will make certain adjustments for what Arsenal will do. One thing that Guardiola has undeniably got right this season, amid many issues he still has to fix or made worse, has been the sleekness of City’s attack. The way that David Silva, Kevin De Bruyne, Raheem Sterling and - most impressively in the last few months - Leroy Sane threaten at interchanging speeds.

Wenger will not use his uncertain future as an excuse for Arsenal's worst run of form in over 20 years

We don’t, however, know what Wenger will do in the face of that. Then again, we don’t even really know what kind of Arsenal will turn up for this match, but recent form suggests one there to be got at and one that could well collapse again.

This is the even greater challenge for Wenger. He doesn’t just have to come up with a plan for City to turn their game back on them, but also has to completely turn around Arsenal.

How he does that is difficult to say, given everything happening at the club right now, but it is just one other case at this particular time where Wenger could draw inspiration or even advice from his great old rival. In his own last decade, and during a period when many people were talking about how the end was both inevitable and required, Sir Alex Ferguson regularly pulled out wins from games that had almost completely been written off.

Wenger has more at stake for Sunday's game (Getty)

This is what Wenger must do this weekend. This is why Arsenal need to play with a greater fire, a greater forensic planning.

The effect of victory would be profound and symbolic, not least because of why they are playing. The effect of defeat would be equally so, most of all because of how the bad run would escalate.