According to ESPN.com, both teams requested to play in Denver the week before their Mexico game so they could get used to the elevation. With Azteca Stadium in Mexico City sitting at en elevation of roughly 7,300 feet, both teams were hoping to they'd get to play in Denver in Week 10 so that they'd have a chance adjust to the high elevation (The elevation at the Broncos' stadium is about 5,280 feet).
Of course, the NFL didn't want to give either team an advantage heading into their Week 11 showdown, so both requests were denied. The biggest loser here probably ended up being the Broncos: Not only did they have to play the Chiefs AND Rams at home this year -- two of the best teams in the NFL -- but they had to play them in consecutive home games. The Broncos played the Chiefs at home in Week 4 and lost 27-23. Two weeks later, they played the Rams at home in a game they ended up losing 23-20.
Although neither team will be spending Week 10 in Denver, the Rams will still be heading to Colorado for a week of practice leading up to their Monday night showdown against the Chiefs on Nov. 19. According to ESPN.com, the Rams will be practicing in Colorado Springs and they'll be using the football practice facilities at the Air Force Academy.