When I was first asked where the Denver's "IN-COM-PLETE" chant came from, I immediately thought back to my very first in-person Denver Broncos experience. Although my parents were avid Broncos fans, there was never enough money to take our large family of five to the stadium. Sure, we'd gone to more than our fair of Denver Zephyr games, but when it came to the Orange and Blue, we always watched from home.
During the 1992 season my father miraculously scored a few tickets from his work and I was blessed to see my first NFL game at Mile High Stadium. Although I can't remember who we played that day, I do remember my reaction to hearing the IN-COM-PLETE chant. The fans put so much energy into screaming it. It was the ultimate group insult. There was no way the opposing QB could pretend he hadn't heard it, no matter how hard he tried. When the chant was immediately followed by the tortured "wanh wanh wanhhhhh" of some high pitched trumpet, it was even better.
With such a spirited following, the chant had to be as old as the team... Or at least as old as John Elway... Right?
After the 42-10 drubbing that the Washington Redskins laid upon the Broncos following the 1987 post-season, Alan Cass took over as the stadium announcer at old Mile High Stadium. He'd had plenty of experience announcing everything from track to basketball to football, in excess of 2,000 events, for the Buffaloes at the University of Colorado. In his time as the Broncos stadium announcer, Cass announced over two hundred consecutive pre-season, regular and post season games. It was sometime within those early few games that IN-COM-PLETE was born. No telling when the "wanh wanh wanhhhhh" that followed it came about.
Cass' streak of games came to an end at the end of the 2007 season when he fell ill with West Nile Virus. Colorado Rockies and Avalanche announcer Alan Roach substituted for Cass while he was ill and took over all Broncos announcing duties at the start of the 2008 season. At the time, it wasn't clear if the chant would endure beyond Cass' tenure. For nearly twenty years a generation of fans had grown up hearing and screaming it. So much a part of the Denver Broncos gameday experience it has even been digitally reproduced in the Madden series of video games.
The mere question that the chant could go away caused fans to voice their displeasure. According to a Denver Post article at the time, David Leach, a Bronco fan from Frisco, Colorado went so far as to create the website, www.saveincomplete.com (now defunct).
Thankfully, Alan Roach and the Denver Broncos have let the tradition endure. Personally, I get great pleasure in thinking that whatever disaster the Oakland Raiders start at quarterback in the years to come will hear Broncos fans mock him every time he throws an... IN-COM-PLETE pass.