ENGLEWOOD, Colo. — Joe Collier, the architect of the Orange Crush defense, passed away Monday night at his home in Littleton, Colorado.

The Broncos' legendary defensive coordinator was 91 years old.

Credited as an early adopter and innovator of the 3-4 base defense, Collier helped Denver to three Super Bowl appearances during his 20-year tenure with the Broncos.

"The architect of the famed Orange Crush defense, Joe Collier is one of the most impactful coaches in the history of the Denver Broncos and regarded among the best defensive coordinators of all-time," the Broncos said in a statement. "He was an innovator in the NFL with his 3-4 defense, helping the Broncos to three Super Bowl appearances during a legendary career with our franchise that spanned more than two decades. Intelligent, modest and soft-spoken, Collier provided steady leadership to five different head coaches as the Broncos emerged as perennial contenders in the 1970s and 1980s. His profound influence on countless players and coaches in Denver included 12 Broncos Ring of Famers, 11 Pro Bowl selections and 2024 Pro Football Hall of Fame linebacker Randy Gradishar.

"Collier's loyalty to the Broncos extended beyond the playing field as a Ring of Fame Selection Committee member for more than 20 years dedicated to recognizing our all-time greats. As we celebrate the extraordinary life and career of Joe Collier, our hearts go out to his three children (Joel, Julie and Lisa) along with his entire family and many friends."

Collier first served as the Broncos' defensive backs coach from 1969-71 before being promoted to defensive coordinator in 1972. His Orange Crush defense helped carry the Broncos to their first playoff berth and first Super Bowl appearance to cap the 1977 season, and he would remain Denver's defensive coordinator until 1988.

During his career with the Broncos, Collier worked for five head coaches, including Lou Saban, John Ralston, Red Miller and Dan Reeves.

As defensive coordinator, Collier guided a slew of talented defensive players, including Pro Football Hall of Famer Randy Gradishar and Broncos Ring of Famers Rich "Tombstone" Jackson, Paul Smith, Billy Thompson, Tom Jackson, Louis Wright, Dennis Smith, Karl Mecklenburg and Simon Fletcher.

"I give a lot of credit to Joe Collier, my defensive coordinator, for creating that 3-4 defense and allowing me to be part of that over my 10 years of playing with the Broncos and Orange Crush," Gradishar said in 2023 after being named a finalist for the Hall of fame. "[I am] very, very glad about that.

"… We were one heck of a defense at that point. We were almost scoring more points than the offense was back then."

Collier's dominant Orange Crush group featured Gradishar, Jackson, Thompson, Wright, Rubin Carter, Barney Chavous, Lyle Alzado, Steve Foley, Joe Rizzo, Bob Swenson and Bernard Jackson as its starters, and the unit allowed ranked third in scoring defense en route to Super Bowl XII. A year later, the defense was perhaps even better, as the group allowed the second fewest points and ranked sixth in yards allowed.

"I think we were the most prepared team I've ever been around," Thompson said in 2002. "Joe was just very meticulous with everything. He taught me the game. The Orange Crush was a name we enjoyed. It was a signature time in Bronco history because we moved from being a team that wasn't respectable to a team that had a chance to win."

Collier quickly developed a reputation for his red-zone and goal-line expertise, but even later in his career, his ever-changing strategy — and steady demeanor — stood out to his players.

"Joe is constant," Jackson said in 1986. "He doesn't raise his voice. He never yells at you when you come off. He just stays calm, and it transfers to us. The guys tend to believe good things are going to happen to us. … Joe's real good at fitting his plan to his personnel."

For a 12th-round pick like Mecklenburg, Collier's ability to adapt to his players made the difference in a 12-year Ring of Fame career.

"I owe my career to Joe," Mecklenburg told the Denver Gazette last year. "He saw a 240-pound nose guard who was a 12th-round draft choice and figured out what I could do. He built a system that just now the rest of the NFL is catching up with where they're using players at different positions and trying to confuse the offense by not substituting. What Joe got everybody to do was to know multiple positions. I had to know seven, and he moved me all around."

Collier also left a lasting impression on one of the greatest head coaches of all time in Bill Belichick. The future six-time Super Bowl-winning head coach spent the 1978 season with the Broncos as an assistant special teams coach and assistant to Collier, and he credited Collier for expanding his knowledge of the defensive side of the ball.

"I learned to see the game through the eyes of Joe Collier and ... Joe, how he had me break it down for him, I could see how he looked at it as a defensive coach," Belichick said in 2020. "That was valuable. Not everybody looks at it quite the same way, but Joe was very skilled at analyzing offenses and what they did and when they did it. He was good at anticipating very well. He did an excellent job of setting that up. I broke down the games for him, but the way he had me do it was a little different than the way I had done it [before]. It gave me a lot of insight there.

"When you coach offense, or when you're a head coach, and you know how defensive coaches think, they don't all think the way that you do, but guys that think like Joe or guys that think like some of the great coordinators and coaches in the league, it's good to just kind of have an idea about how they see the game."

Ring of Famer and two-time Super Bowl champion Mike Shanahan also credits Collier for an early career lesson. Before Shanahan guided Denver as a head coach, he faced Collier in practice as Denver's offensive coordinator from 1985-87.

"When I first came into the NFL, I had a guy who I felt knew it all from a defensive standpoint in Joe," Shanahan told the Denver Gazette in 2023. "Any time you're the offensive coordinator, you always go over the defense and Joe would run the scout team, which was unusual for a defensive coordinator. He was so good at knowing terminology. He knew defenses so well. He was incredible. And he was so accommodating, allowing you to spend time in his office. He always had time, always had a lot of patience."

Before Collier arrived in Denver, he served as the Bills' head coach (1966-68) — leading the Bills to an AFL Championship game appearance in 1966 — and linebackers and defensive backs coach (1962-65). The Bills also won AFL titles in 1964 and 1965. Collier worked for Saban in Buffalo before succeeding him as head coach, and he then rejoined Saban in Denver.

After his 20 seasons in Denver, Collier served two more seasons as the Patriots' defensive coordinator from 1991-92.

Collier continued to live in Colorado following his coaching career and was inducted into the Colorado Sports Hall of Fame in 2002.

The 31-year AFL/NFL coaching veteran got his start in professional football with the Boston Patriots as an assistant to Saban (1960-61) following a brief tenure with Saban's Western Illinois staff (1957-59).

A Rock Island, Illinois native, Collier played collegiate football at Northwestern University, where he set Big Ten records in 1952 with seven touchdown receptions and 650 receiving yards.

The All-American was drafted in the 22nd round of the 1954 NFL Draft, but he served a three-year stint in the U.S. Army and decided to pursue a coaching career following his service.

Collier is survived by his three children (Joel, Julie and Lisa), four grandchildren and four great-grandchildren.

He was born on June 7, 1932.