Both U de Chile and Santos, arguably two of the best sides in South America this season, faced an uphill battle. U de Chile had lost against Deportivo Quito 4-1 in the first leg, while Santos had lost to Bolivar 2-1.
Deportivo Quito plays in Olimpico Atahualpa, 9,222 feet above sea level, where Ecuador's national team has had some of its greatest success beating powerhouses like Brazil and Argentina.
In the past, FIFA has banned games above 8,202 feet.
As for Bolivar, they play in La Paz at over 11,000 feet over sea level. It is precisely La Paz that has stirred the most controversy when it comes to playing in altitude. Players have complained of trouble breathing and splitting headaches.
It's hard to find a more probable explanation as to how clubs that won their first legs could lose by an average of 7 goals when playing away from home. Clubs could grow complacent, they could have less fitness for a two-game series, but altitude and its advantage seem to have a very strong effect.
Various South American teams have complained during the Libertadores when having to visit smaller clubs. In two-leg series like this the damage can be overcome, quite mercilessly as Santos and U de Chile showed, but in the group stage the view is much different and at times many of these smaller clubs advance by dominating at home.
For some, that's simply soccer justice: using whatever means you have to overcome the Goliaths of the world. For others, there are serious implications as to the safety of playing in high altitudes, and the latest string of cardiac problems in soccer should have an impact on those decisions.
For now the players spoke with their skills: the historic victories by both teams will do more to spark the debate than any formal written complaint to FIFA.
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