The Argentina captain was visibly emotional after curling home the opening goal in his side's 3-0 victory in Kansas City, a result that launched the defending champions' title defence in style.

Many assumed the tears were linked to another landmark achievement in Messi's glittering career, but the 38-year-old explained afterwards that the moment stemmed from challenges he had recently faced off the pitch.

"Why did I cry? It was something completely unrelated to football," Messi said.

"I went through some difficult days, but I'm grateful to the entire delegation and my teammates because they were always by my side, giving me a lot of strength to help me get through it."

The emotional moment came on a night when Messi continued to rewrite the record books. His hat-trick was the first of his World Cup career and took his tally in the tournament to 16 goals, drawing him level with Germany legend Miroslav Klose as the competition's all-time leading scorer.

The 38-year-old also became the first player in history to appear at six World Cups, 20 years after making his tournament debut for Argentina.

Despite the records, Messi downplayed the significance of the statistics.

"It's an honour being up there for what it means, being alongside Klose and Ronaldo," he said. "But at the end of the day, they are stats and nothing more."

Messi added that he is relishing every moment of what could be the final chapter of his international career.

"It makes me very happy to have lived through everything that came my way. What I'm living through now is the cherry on top. I'm very happy and grateful for this wonderful group," said the Inter Miami star.

Argentina coach Lionel Scaloni was among those left in awe of another masterclass from his captain.

"At a loss for words about Leo. What can I say? He's incredible," Scaloni said.

"People who watch football want to see him, it's not just Argentines. What he transmits to the world is incredible. As long as Leo wants to, he'll be the best."

Scaloni, however, stressed that the Albiceleste would not allow the convincing win to breed complacency as they continue their quest to become the first nation since Brazil in 1962 to successfully defend the World Cup trophy.

For now, though, the spotlight remains firmly on Messi, whose emotional celebration provided a reminder that even football's most decorated superstar still has personal battles beyond the game.

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