Shots fired. Actually, more than that: Imagine a chopper-mounted howitzer metaphorically blowing out the windows of the executive floors of Barcelona HQ on a moonless night.

Make no mistake: Lionel Messi's decision to take to Instagram and respond to Eric Abidal's interview is a direct challenge to the club's hierarchy. It's also the kind of move that ends one of three ways: Abidal walks his comments back and issues a grovelling apology to Messi and his teammates, Barcelona get themselves a new sporting director (and possibly a new president at the next election), or Messi leaves the club. While that final one is about as likely as Liverpool not winning the 2019-20 Premier League, it is still, theoretically, a possibility.

In fact, were this any other player at any other club, the notion of Messi packing it in wouldn't be so absurd. After all, this is a guy airing the club's dirty laundry in public -- and not just anybody's underpants but those of his boss. (Or, at least, as much as anyone can be the boss of a GOAT candidate with 711 career appearances and 622 career goals under his belt, as well as six Ballons d'Or).

If Messi were upset with Abidal's interview and thought he was passing the buck on the decision to dump former coach Ernesto Valverde last month by implicitly blaming Messi and other senior players -- and there really is no other possible reading of that post -- then the logical action would be to pick up the phone or stride into Abidal's office to confront him. Leaving aside the obvious corporate protocol, the pair have known each for 13 years and were teammates for six seasons. It wouldn't just have been HR-compliant; it also would have been the civil thing to do.

That Messi instead chose to go public straightaway can speak to only one of two things. Either the relationship with Abidal is a lot worse than we thought (and has been for a while), or he is so angry and hurt at being depicted as two-faced (particularly since, in public at least, he always backed Valverde) that he reached for his phone without thinking and tapped away in a blind rage. That, frankly, is distinctly unlike Messi, which is why everyone is taking it so seriously.

Messi is a guy who rarely loses his cool on the pitch, let alone off it. He doesn't speak much, and when he does, it's usually in monosyllables or platitudes. As far as outbursts go, the only thing he has done that comes close to one was when he announced his retirement from international football after the 2016 Copa Centenario, throwing the entire Argentina football association under the bus. That came from a place of fury, hurt and rage. So did this.

Is it the sort of rage that might make him up sticks and go elsewhere? Probably not, but it's worth noting that if Messi wanted to move, he's ideally placed to make it happen. His contract expires in June 2021, which gives him plenty of leverage to seek a move this summer, when he'll turn 33. That's without counting the clause that, as my ESPN colleagues Sam Marsden and Moises Llorens report, could allow him to move as a free agent this summer. While it's pretty much guaranteed that Barca will try to extend his deal, Messi holds all the cards anyway.

Naturally, this puts the club in a very difficult position -- not just where Abidal is concerned but club president Josep Maria Bartomeu, too. After all, you don't become Barcelona president by acquiring a majority stake in the club. You have to be elected by a majority of club members, and all it would take for him to lose the next election -- scheduled for the summer of 2021, but at this rate, don't exclude the possibility of it being moved to July 2020 -- is for Messi to publicly back another candidate. Heck, such is Messi's popularity and standing in the eyes of club members that just about any Messi-backed candidate short of a cardboard cutout or J-Hope from BTS is likely to wipe the floor with him, particularly since Bartomeu himself isn't exactly crushing those approval polls.

That's why in the short term you can expect one of the other two outcomes.

Most likely, Abidal will come up with a face-saving public climb-down and issue a private apology, something along the lines of being misquoted or misspeaking, feeling terrible that Messi was hurt and promising to take better care next time. And if he doesn't? If he takes it on the chin and stands by what he said? At that point, either Bartomeu relieves him of duty and makes Abidal fall on his sword, or they're both out on their backsides when elections roll around. This is not a battle they can win.

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If this isn't handled properly, it risks becoming another annus horribilis for Barcelona that, when you think about it, would be rather grotesque, given that they've won the past two Liga titles, are just three points off the pace this season (despite a rash of injuries, a managerial change and some horrendous performances) and remain among the bookmakers' favorites to win the Champions League, which resumes in two weeks' time. That's more a general indictment of the Bartomeu regime and the cloud of chaos that has enveloped it than anything else.

There's an upshot here, though, one that mustn't be overlooked and that speaks volumes about Messi. It's true: If he threw Abidal to the wolves without speaking to him privately first, it was the wrong thing to do. In fact, it's pretty unprofessional. But on the flip side, let's not lose sight of what motivated this. Messi is angry because his boss implied that he was a prime driver in getting Valverde fired. Because he defended Valverde until the bitter end, it's his word and his integrity that are under attack here.

Messi could easily have let this slide. He could wake up tomorrow morning and still be uber-popular and uber-rich, still playing for the only club he has ever played for professionally, the one he calls home, still in the running to win a Treble, still the GOAT in the eyes of many. But he chose not to. He chose to make it a matter of pride. He chose not to be used. He chose to defend his word, his integrity and his honour.

Money and trophies, goals and accolades: They come and go. The guy staring back at you in the mirror each morning will be with you as long as you're alive, and Messi doesn't want people to think that man is a devious liar who defends his boss in public while stabbing him in the back privately.