Some Argentina players and staff confronted their Spanish rivals after the final whistle of last Sunday's game in New York, which Spain won 1–0 after extra time.
Argentina players, including Atletico Madrid defender Nahuel Molina and former Paris Saint-Germain player Leandro Paredes, were involved in the incidents.
"At the time, I didn't realise it. I was celebrating, hugging teammates," De la Fuente told Spanish television.
"But in any case, it is intolerable, unacceptable, it cannot be allowed. Players of that stature, whom I praised in the days leading up to the match and continue to praise, who are great players with a tremendous coach, surely they must have felt just as bad as we did seeing those reactions."
De la Fuente praised the exemplary behaviour of his own players faced with these "acts of aggression" and "provocations" which he believes could have escalated into more serious incidents.
Although the scenes were filmed and widely shared on social media, they have not yet resulted in any sanctions against the Argentina players.
FIFA has opened an investigation into the incidents to determine whether there may have been violations of the world football governing body's disciplinary code.
FIFA World Cup 2026
The 2026 World Cup took place from June 11th to July 19th in the United States, Canada and Mexico. The tournament featured 48 national teams and was won by Spain, who beat Argentina in the final.
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