​List of all-time greatest coaches makes one thing crystal clear for Broncos legend originally appeared on The Sporting News. Add The Sporting News as a Preferred Source by clicking here.The Denver Broncos have played in eight Super Bowls. They have won three of them. Yet, the franchise still has not had a head coach selected for the Pro Football Hall of Fame.AdvertisementAdvertisementAdvertisementThe fanbase is hoping that will soon change, with former head coach Mike Shanahan, who won back-to-back Super Bowls with the team, standing as the No. 1 candidate. Shanahan was bypassed for that honor this year, but should be on a short list of former coaches to consider for Canton.Recently, Bryan De Ardo of CBS Sports put together a list of who he feels are the 20 greatest head coaches in NFL history. We’re not going to debate the order of his rankings here, but we are going to point out one thing about the No. 16 coach on his list, Shanahan. Here was his analysis:”Shanahan isn’t currently in the Hall of Fame, although his career is certainly worthy of enshrinement. From 1994-98, Shanahan won three Super Bowls, including one as the 49ers ‘ offensive coordinator and two more as Broncos coach. Under Shanahan’s tutelage, Steve Young had one of the best seasons in NFL history, including winning league and Super Bowl MVP honors and throwing the most touchdown passes (6) in Super Bowl history.In Denver, Shanahan helped John Elway cap off his career with back-to-back Super Bowl titles. Shanahan helped surround Elway with a talented supporting cast that included Terrell Davis, a former sixth-round pick who won league and Super Bowl MVP honors while playing in Shanahan’s offense. Davis was the first of several running backs that flourished in Shanahan’s zone blocking scheme.In 1997, Shanahan led the Broncos to an unexpected Super Bowl win over the defending champion Packers in Super Bowl XXXII. By virtue of their win, the Broncos became the first AFC team to win the Super Bowl in 14 years. They also became the second wild card team (and the first since 1980) to win the Super Bowl.Denver successfully defended its title a year later. After a 13-0 start, the Broncos steamrolled through the playoffs while outscoring their opponents 95-32. In Super Bowl XXXIII, with the Falcons focused on stopping Davis, Shanahan used Davis as a decoy and put the spotlight back on Elway, who delivered an MVP performance in what was his final NFL game.Shanahan and the Broncos were unable to recapture their championship pedigree following Elway’s retirement, although they made another Super Bowl run in 2005. Shanahan then produced just one winning season during a four-year run in Washington. His lack of success after Denver’s Super Bowls is likely why he isn’t in the Hall of Fame.Shanahan’s coaching tree, however, might help him eventually earn Hall of Fame induction. His coaching tree includes Gary Kubiak, his son (current 49ers coach Kyle Shanahan) and names like Sean M