Saudi Arabia stuns Lionel Messi and Argentina in the World Cup’s first shock.

LUSAIL, Qatar — This is not how it was supposed to be, but this is how it always seems to end. That slump of the shoulders, that distant stare, that mournful grimace. Argentina came to this World Cup to enshrine Lionel Messi’s legacy in gold. It will remember it, for some time, for one of the greatest humiliations in its history.

A team that had traveled to Qatar on the back of 35 games without defeat, the glow of its first international honor in a generation fresh in the memory, with arguably the greatest player of all time in top form and surrounded by teammates of the highest caliber, opened its tournament with a 2-1 defeat to an opponent, Saudi Arabia, that was supposed to be little more than a sacrificial lamb.

The sting of the defeat — not just a defeat: an embarrassment, a shame, a stigma being carved into Argentine skin in real time — will burn all the more because, by the end, it was nothing if not warranted, ample punishment for Argentina’s inability to pick its way through the Saudi resistance, to keep a cool head, to leverage all of its experience and talent to its advantage.

Saudi Arabia might have ridden its luck in the first half. For much of the second, it picked off an Argentina suddenly addled with all of the old flaws, the old neuroses, haunted by the ghosts of Cameroon in 1990, worried that this World Cup, the one that was supposed to be different, may end up being just like all of the others.