PITTSBURGH — L.C. Greenwood, the relentless defensive end who made up one quarter of the Pittsburgh Steelers’ ‘‘Steel Curtain’’ defense of the 1970s, has died. He was 67.
The Allegheny County Medical Examiner’s office said Mr. Greenwood died Sunday from undisclosed causes at UPMC Presbyterian Hospital.
A six-time Pro Bowler and two-time All-Pro, Mr. Greenwood played for the Steelers from 1969 to 1981, helping Pittsburgh win an unprecedented four Super Bowls in a six-year span. Mr. Greenwood, Joe Greene, Ernie Holmes, and Dwight White formed the bedrock of the defense that helped turn a perennial loser into a dynasty.
‘‘L.C. was one of the most beloved Steelers during the most successful period in team history and he will be missed by the entire organization,’’ chairman Dan Rooney said in a statement. Full story for BostonGlobe.com subscribers.