Brett Keisel has left an indelible mark on the Pittsburgh Steelers

Here is a story that is vintage Brett Keisel.

The Pittsburgh Steelers share a practice facility with the University of Pittsburgh, and one day Keisel sought out Panthers offensive lineman Mike Grimm after watching the man-child lift weights.

Keisel told Grimm, who redshirted last season and has yet to play a down for the Panthers, how impressed he was with his strength and work ethic. He made the kid's day by telling Grimm he has a bright future ahead of him.

Grimm sports one of those beards that is so thin it looks like it was penciled onto his face, and Keisel couldn't resist. He left Grimm by saying with a grin, “Your beard [stinks].”

So does what happened Monday, even if it was inevitable. The Steelers released Keisel, and this time it is probably for good.

Keisel is 36, and his body has started to betray him as it pushes back after more than a decade in the rough-and-tumble NFL. What is astonishing about Keisel's longevity is he felt so lost and overwhelmed at his first training camp that he seriously considered leaving the Steelers.

To say he found himself in Pittsburgh would be an understatement.

Keisel is one of the last survivors from the defenses that led the Steelers to a pair of Super Bowls in a four-season span and served as a bridge to the dynastic teams that won four world championships from 1974-79. The 2002 seventh-round draft pick developed into one of the better 3-4 ends in the NFL and thrived, despite playing a position that doesn't get a lot of glory while on a defense brimming with star power.

Keisel became beloved by fans as much for his steady play as for the persona that started when he grew a beard thick enough to catch Steelers' owner Dan Rooney's attention. It happened in 2010, when Keisel decided to stop shaving while the Steelers made their run to a third Super Bowl in six seasons.

Rooney had been serving as the U.S. Ambassador to Ireland when he saw Keisel's beard on a visit to Pittsburgh. He basically asked Keisel what in the name of Grizzly Adams he was doing, and Keisel offered to shave. Rooney, however, bemusedly signed off on the beard, and it became its own entity. It now has multiple Twitter accounts and has helped raise hundreds of thousands of dollars for Children's Hospital of Pittsburgh.

One of the most famous beards in sports came to represent his personality, and Keisel became the Steelers' ambassador as his career progressed.

Few Steelers players did it better or longer than Keisel, on and off the field.

Keisel, assuming he has played his last down, will be fine -- though for someone ultracompetitve, it will be an adjustment to find something to drive him the way football did for 13 seasons.

His release serves as a grim reminder that time is undefeated, and everyone's time comes in a game dominated by youth.

It felt like the end of an era when the Steelers did not bring back defensive coordinator Dick LeBeau. It feels like even more of one now, with the Steelers sending another strong signal that they are fully committed to getting younger on defense.

If the Steelers are finally moving on from a player who has meant so much to the organization and the city of Pittsburgh, Keisel can be satisfied knowing he wrung everything out of his body and talent. And he left an indelible mark on the only franchise that has won six Super Bowls.