A security oversight leaked the passport details of every player in the Argentina squad for Tuesday's pre-World Cup warm-up friendly against Iceland, including Lionel Messi, media reports said.
The passport numbers, listed on the official team sheet, should have been blurred before being released to the media and the public. But in Alabama's Jordan-Hare Stadium, they were circulated without redaction.
Reuters has contacted the Argentinian football federation for comment.
Argentina won the match 3-0 in front of more than 88,000 people, as Messi marked his return from a hamstring injury by scoring within two minutes of coming on in the second half.
Lautaro Martinez was fouled in the box after receiving a through-ball from Messi.
Messi calmly converted the resulting penalty to put his team 2-0 ahead and became Argentina's oldest goalscorer at the age of 38 years and 11 months, two months older than Angel Labruna, who had held the previous record since 1957.
"I'm happy, savouring every moment and excited as ever," said Messi ahead of his record sixth World Cup appearance.
Argentina will kick off their title defence with a Group J match against Algeria on Tuesday.

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