Read an article by a Pulmonologist-and Ram fan-who said that this can cause damage down the road. Apparently its not a matter of oxygen which is always at 21% no matter the elevation. But the oxygen cells get further and further apart as the elevation increases thus increasing the barometric pressure needed to get the oxygen into the lungs. Once that happens it takes weeks before the pressure one is used to can return to its normal level. Therefore immediate games in the future might be compromised. His advice was to get the team back-assuming they did go to Denver-ASAP.
How the Broncos handle this is a mystery to me.