The 38-year-old's brace took his tournament tally to eighteen goals, surpassing Miroslav Klose's previous record of sixteen and making him the highest scorer in the history of the competition across both the men's and women's game.
He was indebted to the miss that came first. With just five minutes played, a VAR review identified a foul on Lautaro Martínez inside the penalty area and Messi stepped up with the record in his hands. He sent the ball wide left of goal and stood with hands on knees as 70,649 supporters in Dallas groaned.
What followed was the kind of response that has defined his career. On thirty-eight minutes, Thiago Almada cut inside from the right and laid the ball across the face of goal — Messi arrived to finish first time and write himself further into football history.
Austria improved after the break and Marcel Sabitzer's free-kick tested Emiliano Martínez, but the goalkeeper held firm to preserve a lead that always felt sufficient. The match's decisive moment arrived deep into stoppage time when Messi collected possession, had an initial effort blocked, and tucked the rebound home for his eighteenth goal in World Cup football.
Speaking to Telemundo, Messi was candid about the emotional weight of the evening.
"To be honest, I'm really happy about the win, especially as it's such a crucial victory, hard-fought and well-earned, but one that gives us peace of mind for what lies ahead. This is the World Cup; it was a very evenly matched, very intense match, and we're happy to have picked up six points and to have already qualified."
Asked whether the goal he scored to break the record was his favourite at the tournament, he gave an honest answer.
"I don't know, to be honest, I can't remember right now; I'm tired, I'm running low on energy, and I'm finding it hard to think, so anyway, I'm just going to enjoy this moment, and I'm looking forward to celebrating with my team-mates."
On the missed penalty, he offered a philosophical reflection.
"I am enjoying this moment and seeing how far we can go together. Today I had the penalty, but maybe I wouldn't have scored the others if that had gone in."
Argentina head coach Lionel Scaloni addressed Messi's value to the team beyond the statistics.
"It's logical that it's a blow not converting a penalty but knowing that at the moment of switching on … when Leo switches on, everyone does. And I think that's a strength also of the team. Even today when the team were suffering without having the ball, he was working and won a ball in the goal — you could see his commitment."
Midfielder Alexis Mac Allister was similarly effusive.
"What I'd say is that seeing him on the pitch, at the same level, is something else entirely. The things he does are simply unbelievable — the way he reacts in the final moment to whatever's happening. So, yeah, nothing more to add — happy that he can be out there enjoying it and scoring the goals."
Austria remain in contention for the knockout rounds on three points. They face Algeria in Kansas City in their final group game, knowing a win could still be enough to progress.