Azteca Stadium is the worst place to ever play a sporting event.
The first NFL game in Mexico in 11 years will be held tonight in the the capital city's Estadio Azteca as the Houston Texans and Oakland Raiders face off.
The NFL wants this to be a yearly event. But soccer stars who have played here before say the stadium can be a nightmare for athletes due to thin air and heavy air pollution, USA Today reports.
The NFL seems excited, though. (That hashtag translates to "My game, my NFL.")
Texans fans have already arrived en masse.
Part of the reason for athletes' concern is the heavy air pollution in Mexico City. You can barely see the stadium through the haze on the left in this photo from March.
Forget Mile High
The other major challenge for athletes is the extreme altitude of the stadium. The Denver Broncos' Sports Authority Field at Mile High is, you guessed it, a mile above sea level, which makes it by far the highest NFL stadium.
Meanwhile, Estadio Azteca is 7,280 feet above sea level, which makes it 2,000 feet higher than Mile High. That means the air will be so thin, even pro athletes could have trouble keeping up.
Expect to see a lot of oxygen masks, like this one from a Broncos player in 2012.
For this game, teams arrived Sunday to better acclimatize to the high altitude.
The downside of football vs. soccer
Former U.S. soccer player Eric Wynalda said the stop-and-start nature of football, as opposed to the relatively continuous play of soccer, will actually hurt the athletes more.
"You don't really feel it until you stop... You almost feel like you are going to pass out," he said. He added that hulking linemen could have more trouble getting enough oxygen than relatively smaller soccer players.
The fans appear to be ready to go regardless. The game sold out back in July, according to the NFL. Both teams lead their divisions.
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