Former Steelers running back Sidney Thornton died at the age of 68, the team announced on Wednesday.

Thornton played six seasons in the NFL, all with the Steelers. During that span from 1977–82, Thornton won two Super Bowl titles with the team in ‘79 and ‘80.

In his six-year career, Thornton appeared in 74 games but started in just 21. He finished his career with 1,512 rushing yards on 356 carries and 18 rushing touchdowns. Additionally, he caught 46 passes for 515 receiving yards and six touchdowns.

Thornton played collegiate football at Northwestern State in Louisiana before being selected by the Steelers in the second round of the 1977 NFL draft. In 1986, Northwestern State honored Thornton by inducting him into the school’s N-Club Hall of Fame.

The running back joined the USFL for one season in 1984 after retiring from the NFL. That year, Thornton finished with 288 rushing yards and four touchdowns on 101 carries, along with 175 receiving yards and one touchdown on 25 catches.