But in 1977, a civic virus called Broncomania struck when the usually downtrodden Broncos stunned the football world by winning 12 of 14 regular-season games and then wiped out the defending Super Bowl champion Oakland Raiders in the AFC Championship Game to earn a berth in Super Bowl XII.

The Orange Crush defense was the heart of the surprising Broncos. (Provided to SportsLine)

You want to talk about crazy? The day the Broncos beat the hated Raiders 20-17 at Mile High Stadium, nurses at Denver's Mercy Hospital wrapped all the newborn infants in orange receiving blankets. One guy painted his house bright orange. In nearby Pueblo, all members of the city council dressed in orange for their town meetings. An estimated 450,000 orange t-shirts were sold in area department stores during the 1977 season.

"It was like a year-long high school homecoming," one fan said.

"That was a lot of fun that year," said longtime Denver defensive coordinator Joe Collier, opting not to let the fact that Dallas spoiled the party with a 27-10 victory in that Super Bowl cloud his judgement.

Before 1977, Denver had fielded a pro football team for 17 years - 10 in the AFL and seven after the merger with the NFL - and it had enjoyed two winning seasons, the best being 9-5 in 1976. But Red Miller took over the team in 1977, he kept Collier as the defensive coordinator, and Collier put together the Orange Crush defense, a 3-4 concoction that was as good as any 3-4 in history.

"In the mid-70s we had a good defense in Denver because we had great speed," Collier said. "We were a little bit undersized, but we probably had the best speed in the league. And we were playing the 3-4, which lends itself to those types of players. They're able to run all over the place and you can do lots of things, stunting and shifting. And the other thing that made us so good was the fact that they played together for a long time, the same guys, and that solidified them into a pretty good defense."

The defense began to come together in 1973 with the drafting of players such as linebacker Tom Jackson and defensive end Barney Chavous. Linebacker Randy Gradishar came in 1974, cornerback Louis Wright, nose tackle Rubin Carter and safety Steve Foley were picked in '75, and free safety Bernard Jackson was drafted in '77. Linebackers Joe Rizzo ('74) and Bob Swenson ('75) were brought in as undrafted free agents. This group joined longtime cornerback Billy Thompson and defensive end Lyle Alzado in the starting lineup for most of 1977, and Collier coordinated them into a fast, hard-hitting unit that dominated opponents as they allowed a league-low 148 points.

"It was fun because we knew we could keep people under a certain amount of points," Collier said. "Just as long as the offense didn't turn the ball over too much or they scored 20 points, we knew we were going to win a lot of games."

Denver won its first six games, and a Week 5 victory over the Raiders, a 30-7 rout in Oakland, was the game that showed the rest of the NFL the Broncos were for real.

"We went out and played Oakland, and they had just won the Super Bowl the year before," Collier said. "We had seven interceptions and we threw a touchdown pass to our field goal kicker, Jim Turner. That game kind of pushed us over the top in '77."

The front three consisted of Alzado and Chavous on the ends and Carter in the middle over the center, the prototypical nose tackle.

SPOTLIGHT

Randy Gradishar

"They were very active guys and they could run, and that's what I liked about them," Collier said. "I've seen a lot of 3-4 defenses in the league, and there have been some good fronts, but I'm a little prejudiced; I liked them best."

The linebacking crew was led by Gradishar, one of the surest tacklers ever, a man who topped 250 tackles in a couple of seasons. Jackson, the longtime ESPN analyst, was also a superb tackler who could also defend the pass. Rizzo and Swenson were hustle guys, always around the ball.

"All four of those guys were intelligent," Collier said. "They knew what each other was doing and they worked as a unit."

Gradishar had been a first-round selection out of Ohio State and he was supposed to become a great player. Jackson came in the fourth round out of Louisville and far exceeded expectations. Both players are enshrined in the Broncos' Ring of Fame.

"Nobody was very high on Tommy, really," said John Ralston, a former Denver coach who was in charge of the draft during this period. "But I saw him in the Blue-Gray Game and I thought, 'This kid can play!' He was only 5-11, but I couldn't take my eyes off him. When the time came to draft in the fourth round, he was still available. Now, I always thought the fourth round was the best one to take a gamble, so that's what I did with Tommy. The minute Tommy stepped on the field, he was the best player out there. He was hell on wheels."

In the secondary, Wright was another nugget Ralston unearthed in the draft, and he teamed with the veteran Thompson to form a sticky coverage duo. Foley and Jackson took care of the last line at safety.

The new breed Broncos, who won two Super Bowls in the late 1990s, know that fans still revere the Orange Crush defense of the late 1970s, and it drives them to succeed.

"Oh, yeah," said linebacker John Mobley. "I've been here for five years, so I know about the legend of the Orange Crush defense and the tradition they had."

Photos courtesy of the Denver Broncos