"We have informed Brett Keisel that we plan to release him today," Steelers General Manager Kevin Colbert said in a statement. "We appreciate his efforts and we are grateful for what he helped us accomplish, including two Super Bowl Championships."
Keisel, 36, suffered a torn triceps injury last season, which limited him to 12 games and only four starts.
He was due $1.5 million this season, the final year of his contract, and Keisel's release could signal the end of his career.
Though it can be tough to identify football players without their uniforms on, and names sewed into the back of their jerseys, Keisel was one of the easiest players on the Steelers roster to spot on or off the field because of his giant beard.
The 6-foot-5, 285-pounder was drafted by Pittsburgh out of Brigham Young with the 242nd pick in the seventh round of the 2002 draft. He became a regular starter in 2006 after beginning his NFL career on the special teams unit.
Over 13 seasons with the Steelers, Keisel recorded 30 sacks -- one of only 12 players in Pittsburgh history -- while knocking down 36 passes. He also forced seven fumbles, recovered another seven, and came up with two interceptions. He was named to the Pro Bowl in 2010.
Keisel won Super Bowl XL and XLIII with Pittsburgh as well as three AFC championships (2005, 2008, 2010).
"We will always consider him an all-time Pittsburgh Steeler," Colbert said.
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