By Keith Coffman
DENVER (Reuters) - When the Denver Broncos first took the field as charter members of the fledgling American Football League in 1960, the rag-tag team's mustard-yellow jerseys, chocolate brown pants and vertically-striped socks were a source of derision.
Unfortunately for the club's small but loyal fan base, the Broncos' on-field performance matched their comical uniforms, as the team did not post a winning season until 1973, three years after the AFL merged with the National Football League.
Denver will face the Carolina Panthers in Super Bowl 50 on Sunday, marking the franchise's record-equaling eighth appearance in the NFL's championship game, tying them with the New England Patriots, Dallas Cowboys and Pittsburgh Steelers.
The Broncos' rise to elite status from their roots as perennial door mats can be attributed in large part to the team's owner since 1984, Pat Bowlen, who relinquished control in 2014 after announcing he was suffering from Alzheimer's disease.
Seven of the team's Super Bowl appearances, among them two NFL titles, have come under the ownership of Bowlen, 71, who created a family trust a decade ago to ensure the team will remain in the hands of one or more of his seven children.
Despite the early losing years when Denver had no other teams in major league professional sports, the Broncos always had a zealous following in the Mile High City, which Bowlen always understood, according to Jim Saccomano, the club’s former longtime director of communications.
"The Broncos are the state religion in Colorado and are the soul of the city," said Saccomano, who has written two books about the team's colorful history.
The Broncos have sold out every home game since the 1970 merger, thousands are on a waiting list for season tickets and Forbes Magazine lists Denver as the league's 11th most valuable franchise, worth an estimated $1.94 billion.
Bowlen, who once was a fixture at the team's headquarters and frequently seen on the sidelines during games, was absent when his team was awarded the American Football Conference trophy after their victory over the New England Patriots on Jan. 24.
The team's day-to-day operations are now in the hands of team president and chief executive Joe Ellis, and general manager John Elway, the Broncos' Hall of Fame quarterback for their two Super Bowl wins.
In addition to consistently fielding competitive teams under his ownership, Bowlen is well respected by the league's other owners, and also at the NFL's head office.
When it was announced that Bowlen was stepping aside due to poor health, NFL Commissioner Roger Goodell credited the Denver owner for playing a leading role in the league's immense popularity.
"From building a championship team that is a pillar of the community to his important work for the league on television and labor matters, Pat's love of the game drove him and we have all benefited from his passion and wisdom," Goodell said.
(Editing by Mark Lamport-Stokes)