The crossover between "American Idol" and football fans is not a good one.  "Idol" host Ryan Seacrest learned that the hard way Thursday night after he was introduced to the Fans before the season kick-off.

The excitement Seacrest tweeted about before the game may have disappeared once he was introduced to the crowd.   As soon as he was announced, the boo-birds came out in force.

But Seacrest is a pro, and seemed un-phased.   "So come on Denver, let's join these football greats representing all 32 teams, and ring in the NFL season." he yelled.