Martin Rogers

USA TODAY Sports

MEXICO CITY – As the National Football League seeks to further broaden its international reach with Monday’s clash between the Oakland Raiders and Houston Texans, the match-up is already guaranteed to be the high point of the season in one regard.

Azteca Stadium sits at 7,280 feet above sea level, higher than Denver’s Sports Authority Field at Mile High, which is by far the NFL’s most-elevated venue at 5,280 feet. The height, plus the atmospheric conditions of Mexico’s capital, could cause significant issues for the players.

“Azteca Stadium is the worst place to ever play a sporting event,” former United States national team soccer star Eric Wynalda told USA TODAY Sports.

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“You can’t breathe. The pollution is so bad that if you don’t have some form of rain that’s brought all that down you are going to be sucking wind.

“They (will) break a record for how many oxygen masks they have on the sidelines. The combination of being that high up with pollution is just devastating to the body.”

The U.S. soccer teams Wynalda played on are among many sporting visitors to the venue that have struggled desperately. The altitude of Mexico City, added to the smog that accumulates in the bowl-like natural topography that surrounds it, gives home teams a huge advantage.

Both the Raiders and Texans are in the same position of unfamiliarity, each being coy on the measures they are using to combat the elements. Local sports medicine and respiration doctor Jorge Avendano Reyes warned that the players are in for a rough ride.

“There can be headaches, dizziness, sensation of fatigue, accelerated heartbeat, hyperventilation,” Reyes said. “We can also have respiratory symptoms, when we are exposed often to the pollution.

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“The amount of oxygen that reaches the cells decreases, leading to the faster heartbeat and cardiac activity. The body tries to ventilate more quickly.”

The Azteca is an iconic venue in Mexico, the only stadium to have hosted two soccer World Cup finals. Teams familiar with the surroundings claim that the complaints of visitors are nothing but sour grapes. Yet science suggests otherwise.

Reyes said bigger players such as linemen would find things more testing than leaner athletes, while adding that typical oxygen masks may do little to help aid respiration.

“We’re on an equal playing field,” Texans offensive lineman Duane Brown said. “No one’s more used to the altitude than the other team, so we’re all going out there with the same struggle, if there will be a struggle.”

Some players believe the slower pace of American football, rather than the constant movement of soccer, may help lessen the effects. Wynalda disagrees.

“You don’t really feel it until you stop and when your heart starts to beat and tries to slow down,” Wynalda said. “You just have these moments where you click out. You almost feel like you are going to pass out. The players stop for a second, you try to catch your breath, and then it is almost like you’ve just had a very long blink, and something bad happens.

“For American football I really am curious to see how these guys handle it. It is going to have a massive effect on their body. These are some big bodies out there, 300 pounds people who are trying to get oxygen into their muscles and to their brains. I think you will see a lot of delay of game penalties.”

Conventional wisdom suggests that teams should either come in two weeks early to allow the body to adapt to the conditions – or very late to reduce the amount of time for the elements to make an impact. Given that the former option was impossible, both teams were due to arrive on Sunday.

