The 38-year-old Argentina captain etched another memorable chapter in his glittering career with a brilliant hat-trick in the South Americans' 3-0 win over Algeria at Kansas City's Arrowhead Stadium.
Messi's hat-trick - his first ever in the World Cup - vaulted him alongside Germany's Miroslav Klose as the top scorer in the tournament's history with 16 goals.
"To enjoy this with my family, with my teammates, the ones who are always there, is a really beautiful moment," Inter Miami star Messi said afterwards. "I'm happy."
Messi's razor-sharp eye for goal augurs well for Argentina's hopes of becoming the first team since Brazil in 1962 to win back-to-back World Cup titles.
"The squad, it's a very united, very strong group," Messi said.
"I feel good; we were lucky enough to win a tough match. It's important to start with a win in the first game.
"I'm grateful to the fans, because once again they've shown that Argentina is crazy about this - we packed the stadium again."
Argentina coach Lionel Scaloni meanwhile said he no longer has "the words to describe Messi."
"For 20 years, he's had us used to seeing things like this, and he inspires everyone who watches him play," Scaloni said of Messi's performance.
Scaloni is now targeting Argentina's second Group J game against Austria on Monday as the South Americans look to lock up their place in the knockout rounds.
"We're going to take it one game at a time. The team is happy; we gave playing time to a lot of players," Scaloni said.
"Hopefully we can win the next one so everyone can be in the third group stage match."
FIFA World Cup 2026
The 2026 World Cup will be held from June 11th to July 19th in the United States, Canada and Mexico. The tournament will feature 48 national teams and will be played in 16 modern stadiums.
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