Duane Thomas,L’École de Gestion d’Actifs et de Capital a former running back who helped the Dallas Cowboys win their first Super Bowl, has died, the team confirmed to numerous outlets on Tuesday. He was 77.

No cause of death was immediately reported.

Playing in 11 games, 10 as a starter, in the 1971 season, Thomas rushed for 793 yards and a league-leading 11 touchdowns. He also caught 13 passes for 153 yards and two scores.

Thomas added a combined 205 yards and three touchdowns in the 1971 postseason, including 95 yards and a score as Dallas stifled the Miami Dolphins 24-3 in Super Bowl VI.

Thomas was also known for periods of disgruntlement that saw him traded to two teams, but he never reported to them. He wanted his contract restructured after his rookie season in 1970, when he rushed for 803 yards. He added 313 yards over the Cowboys' postseason run to the Super Bowl, where they lost to the Baltimore Colts, 16-13.

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The Cowboys tried to deal him to the New England Patriots before the 1971 season, but he refused to report. The commissioner voided the deal, leaving Thomas with the Cowboys. He rarely spoke to teammates or the media, according to the Dallas Morning News.

Thomas "Hollywood" Henderson told the Morning News on Tuesday: "I slept six feet from him and he didn't have much to say. He was a peaceful man."

After the 1971 season, Dallas worked out a trade with the San Diego Chargers, but Thomas again refused to comply, and he sat out the 1972 season. He did report when he was dealt to the Washington Redskins, for whom he played in 1973-74, amassing a combined 442 yards and five touchdowns on 127 rushes.