That of course comes with caveats: He has played most of their games in that time, so the chances for them to succeed without him have been relatively limited. Arsenal have also shown themselves capable of aching spinelessness even with him in the team.

But he was absent for the defeat to Stoke in September, the loss at Watford in October, and on Sunday he was left at home, his exit seemingly imminent, for the dispiriting 2-1 loss at Bournemouth. Arsenal's prospects in a post-Sanchez world do not look especially bright.

Arsenal showed at the Vitality Stadium exactly why Sanchez is so keen to play his football for Manchester City. Or Manchester United. Or anyone else, really. This was a performance that showed off a heady combination of a limp attack, a membrane-thin defence and only Jack Wilshere, a player who had a so-so season for Sunday's opponents last term, showing any real invention in midfield.

The question now is not whether Arsene Wenger can turn this around, or when he should go, but whether this Arsenal team are actually in a better state than when he arrived in 1996. Arsenal as a club -- or at least this version of it -- were built by Wenger, and the joy he has given their fans in the last two decades mean that the bust of the Frenchman's head should stay long and proud where it does now inside the Emirates.

But when he arrived, Arsenal had David Seaman in goal, that defence of Lee Dixon, Steve Bould / Martin Keown, Tony Adams and Nigel Winterburn, doughty club servant Ray Parlour in midfield, Ian Wright up front and the genius of Dennis Bergkamp just behind him. The previous season they had finished fifth: not outstanding by any means, but would anyone really back the 2018 team to finish above City, United, Tottenham, Chelsea and Liverpool?

In previous years you could argue that Wenger's management was the problem, because he wasn't getting the best from a talented group of players. That problem remains, but minus Sanchez, and probably Mesut Ozil -- who shows little sign of remaining in the summer -- is there even any real enviable quality in the team that Wenger has created, and will bequeath to his successor?

Sanchez and Ozil aside, how many of this team would the rest of the top six want? Hector Bellerin would be of interest to a couple. Someone might think they could do something with Alex Iwobi. Wilshere, at a push? Beyond that, it's thin gruel.

How many have improved under Wenger? Bellerin again? That's about it. The rest are either at a similar level to when they arrived at the club, or they have talents that have not progressed beyond "promising". Every other manager in the top six, for all their faults, can at least count a few players in their respective teams who have got better under their tutelage.

Had Wenger gracefully stepped aside a couple of years ago, after winning the FA Cup in 2014, he could have done so with a little dignity. The decade-long trophy drought was ended, and even though his prime had disappeared in the winds of the post-Emirates financial reticence, he would have wandered back to France, or perhaps upstairs at Arsenal, with the best wishes of everyone. He has now almost certainly alienated a generation of fans who don't really remember the good times, and on the way to spoiling the recollection of those that do.

If he goes in the summer, he will not only hand over a diminished Arsenal, but possibly strengthened rivals too. It almost didn't matter if Arsenal sold Sanchez to Manchester City or United. As Wenger has insisted on making clear, they're competing on a different level both financially and in a football sense: if the Chilean returns to Pep Guardiola then it will weaken Arsenal, but in reality not beef up those they're in direct competition with.

United are different. Arsenal are supposed to be able to compete with United, not hand over their best player -- again. If Sanchez runs down his contract and joins United in the summer anyway then so be it, but if he goes there with Arsenal's acquiescence, it makes them look even weaker. Sure, they'll have a few more pounds in the bank account, but how much does that really matter in the wider scheme of things?

Wenger used to look agitated after defeats, but after the Bournemouth game, he had the relatively relaxed face of a man used to this routine. And yet his words were those of a manager speaking after an eyebrow-raising loss, a bump in the road, the exception rather than the tedious, inevitable, endlessly repeating rule.

"We made two very surprising mistakes, not even forced errors," said Wenger, revealing himself to be the only person watching who was surprised by any of what had just occurred. "Overall we come out of the game and you think 'how did we lose the game'? That's basically it."

"It's very frustrating," he continued. "It's a very disappointing result for us. Especially when you're 1-0 up and we made mistakes in areas where you wonder where they come from."

While it's always tricky to take stuff like this at face value, and you don't know what truly happens behind the closed dressing room door, this all paints the picture of a man who doesn't know why things are going wrong and sure as hell doesn't know how to fix it. That alone proves he's no longer the man for the job.

A few minutes after Wenger departed from his postmatch news conference, Alex Oxlade-Chamberlain, the man who left Arsenal for Liverpool in frustration and under Wenger had stagnated horribly, skipped around a couple of Manchester City players and banged one into the bottom corner from 25 yards.

The secret to good tragedy, as well as comedy, is timing.