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The NFL has lost one of the most innovative assistant coaches of his time, with the Denver Broncos announcing Monday that longtime offensive line coach Alex Gibbs has died due to complications from a stroke. Gibbs, 80, had not coached in the NFL since 2013, but spent 27 seasons at the professional level, serving eight different teams after nearly two decades in college football. He's perhaps best known as the man behind the Broncos' innovative zone-blocking scheme, which helped propel Denver to two Super Bowl championships in the 1990s.

"We are deeply saddened by the passing of Alex Gibbs, who had a profound impact on the Denver Broncos and the National Football League as an offensive line coach," the Broncos said in a statement. "During his 14 years with the Broncos, Coach Gibbs left a lasting legacy on this league with his innovative blocking schemes and outstanding teaching ability. He helped the Broncos to Super Bowls during three different decades -- including back-to-back world championships -- while forging a reputation as one of the greatest assistant coaches in NFL history."

Gibbs' first NFL job coming out of the college ranks, where he'd spent time with seven different schools as an assistant coach, was with the Broncos. Hired to coach the club's offensive line in 1984, he held the position for a total of 13 seasons -- first from 1984 to 1987, then again from 1995 to 2003. His second stint is the most notable. Coming after brief stops with the Raiders, Chargers, Colts and Chiefs, it saw him usher in an unconventional blocking scheme -- prioritizing smaller, faster linemen over bigger, more traditional blockers. As a result, the Broncos enjoyed six straight seasons with a 1,000-yard rusher (1995-2000), unlocked future Hall of Fame running back Terrell Davis, and witnessed some of quarterback John Elway's finest moments en route to back-to-back Super Bowl wins in 1997 and 1998.

Gibbs, who also served as an assistant head coach with the Falcons (2004) and Texans (2008-2009), returned to the Broncos as an offensive consultant in 2013, when Peyton Manning and Co. appeared in a second straight Super Bowl. He was previously hired by the Seahawks in 2010 as an assistant head coach under Pete Carroll but retired just before the start of the season.