The Liga MX first-leg playoff match between Club America and Leon has been postponed and moved due to poor air quality in Mexico City.
America and Leon were originally planned to face off at the Azteca Stadium on Wednesday night, but the city's environmental commission announced the Extraordinary Atmospheric Environmental Contingency Plan due to the low quality of the air.
The commission advised residents to avoid outdoor activities and Mayor Claudia Sheinbaum Pardo said she would consider cancelling school classes if the pollution, caused in part by forest fires in surrounding areas, got any worse.
The fires, aided by Mexico City sitting in a valley with little wind to push the smoke away, has left the city in a haze for several days, with the pollution getting so bad that it is considered a risk to human health.
As such, Liga MX was forced to move the match.
The league announced that the initial plan was to play at the Nemesio Diez Stadium, in the city of Toluca, only to have bad weather rule that option out.
That left the third option, Estadio Corregidora in Queretaro, as the landing place for the semifinal first leg contest.
The second leg is still scheduled to take place in Leon on May 19.
Leon won their way into the semifinal round with a dominant showing in the quarterfinals against Club Tijuana, winning the first leg 3-1 and the second leg 2-1 for a 5-2 aggregate victory.
America also looked strong in their quarterfinal, winning the first leg 3-1 before a narrow 1-0 loss against Cruz Azul in the second leg as they pulled off a minor upset having finished the season one place behind their opponent.
Leon entered the playoffs as the top seed, having rolled to 41 points over 17 matches, while America finished fifth 29 points.
The winner of their tie will take on either Monterrey or Tigres in the final, with the first leg of the Clasico Regio semifinal set to take place on Wednesday night as scheduled.