Mexican fans used a chant widely regarded as homophobic during Tuesday night's World Cup round of 32 match against Ecuador.
The chant, a one-word slur that translates to "male prostitute" in Spanish, is typically shouted when the opposing goalkeeper takes a goal kick.
Supporters first used the chant in the fifth minute as Ecuador goalkeeper Hernán Galíndez prepared for his first goal kick of the match.
It marked the second time during the tournament that the chant has been heard. FIFA has previously fined the Mexican Football Federation several times over the use of the offensive chant by supporters.
The chant first emerged during an Olympic Games qualifying match between Mexico and the United States in Guadalajara and gained international attention during the 2014 FIFA World Cup in Brazil.
The atmosphere surrounding the match had been tense even before kickoff.
Late Monday night and into the early hours of Tuesday, Mexican fans gathered outside Ecuador's team hotel in Mexico City, using horns, drums, motorcycles, cars and DJs to create noise in an apparent attempt to disturb their opponents.
The rivalry between the supporters also reflects wider political tensions between the two countries.
Diplomatic relations between Mexico and Ecuador have remained severed since April 2024, when Ecuadorian police raided the Mexican embassy in Quito to arrest former Vice President Jorge Glas, who had been granted political asylum there.
Although Ecuadorian President Daniel Noboa recently said he was willing to restore ties, Mexican President Claudia Sheinbaum said last Monday that she would not discuss the issue until after the high-profile World Cup match.