PITTSBURGH (AP) _ Steve Furness, who earned four Super Bowl rings as a member of the Pittsburgh Steelers' famed Steel Curtain defensive line, has died of a heart attack. He was 49.

Furness was stricken at his suburban Pittsburgh home Wednesday night and was pronounced dead at St. Clair Hospital a short time later.

A defensive tackle with the Steelers from 1972-80, Furness replaced Ernie Holmes on one of the best defensive lines in NFL history. He played alongside Joe Greene, L.C. Greenwood and Dwight White.

``He was an important part of one of the greatest teams of all time,'' Steelers vice president Art Rooney said today.

Furness earned championship rings for Super Bowls from the 1975, 1976, 1979 and 1980 seasons. In a recent poll, viewers of ESPN voted the Steelers of the 1970s the top NFL franchise ever.

Furness attended Rhode Island and was drafted in the fifth round by Pittsburgh. He played nine seasons, starting 49 games, and recorded 32 sacks.

He was one of 22 players to play on all four Steelers championship teams.

After retiring, Furness was an assistant coach at Michigan State from 1983-90 and a line coach for the Indianapolis Colts in 1991.

Furness returned to the Steelers in 1992, replacing Greene as a defensive line coach on Bill Cowher's first staff after taking over for Chuck Noll. Cowher fired Furness following the 1993 season, when the Steelers were 9-7, then lost in overtime to Kansas City in the playoffs.