Ryan Clady, one of the two best left tackles in Denver Broncos’ history and one of its three-best offensive linemen overall, announced his retirement Tuesday.

On Twitter, Clady posted a photo of himself in his Broncos’ uniform No. 78 coming out for the starting lineup introductions with the message: “Despite having several teams who are currently interested in signing me, I have made a very difficult decision to retire from my NFL playing career.’’

Clady thanked family, friends, teammates and coaches but mentioned just one person by name: Pat Bowlen, the Broncos’ owner, “for bringing me into the NFL.’’

It goes fast. Entering the 2008 NFL Draft, then Broncos’ football operations boss and coach Mike Shanahan zeroed his sights on one of three left tackle prospects for his No. 12 overall pick in the first round – Clady, Chris Williams and Brandon Albert.

Shanahan picked the correct one in Clady, who came out of Boise State. Williams never did emerge as a left tackle. Albert was a two-time Pro Bowler who announced his retirement Monday.

Although Clady was 6-foot-6, 309 pounds, Shanahan couldn’t stop talking about his incredibly nimble feet.

Clady also benefitted from long arms, especially as a blind side pass protector.

“Really long arms,” DeMarcus Ware, one of the best pass rushers in NFL history, once said of Clady. “That’s what made him tough was those long arms.

You think you have him beat and—hey now!—he’d reach out and get you.”

Clady’s arms are 36.75 inches long. By comparison, Cleveland’s Joe Thomas, who is widely considered the best left tackle of the 21st century, had 32.5-inch arms—more than 4 inches shorter than Clady’s reach.

Clady was not only a four-time Pro Bowler, he and former center Tom Nalen are the only Broncos’ offensive linemen who were twice named first-team All Pro.

Clady never missed a game in his first five seasons but he would have just six healthy seasons overall.

If not for misfortune with injuries, Clady may well have played a few more years and his retirement would have started a five-year countdown to the Pro Football Hall of Fame.

Although drafted for the zone-blocking scheme, Clady only got to play one year in his preferred system as Shanahan was fired after the 2008 season. In 2015, when Gary Kubiak brought the zone-blocking system back to Denver, Clady tore his ACL on the first day of organized team activities (OTAs).

Not suited for the power-gap blocking system preferred by head coaches Josh McDaniels and John Fox, Clady nevertheless helped Willis McGahee, Tim Tebow and the Broncos lead the NFL in rushing in 2011.

The Broncos played in two Super Bowls during Clady’s term, but each time he suffered season-ending injuries and didn’t play in the Big Game to cap the 2013 and 2015 seasons.

Although his career may have fallen short of getting his bust bronzed in Canton, Clady figures to be a strong candidate for the Broncos’ Ring of Fame when he becomes eligible in 2022.