NFL back up linebacker Godfrey Myles, best known for the six years he spent with the Dallas Cowboys, died in Miami on Thursday after suffering a massive heart attack, ESPN reports. Once a college teammate of Hall of Famer Emmitt Smith at the University of Florida, Myles’s career took off after being drafted by the Cowboys in 1991. With his help, the Cowboys took home three Super Bowl wins in four years.

His biggest year is said to have been the team’s 1995 Super Bowl win against the Pittsburgh Steelers. During the 11 games he started that season, Myles outdid himself with forced fumbles and fumble recoveries and 75 tackles. He retired from the sport following the 1996 season as he suffered an injury from a torn ligament in his knee.

While the source of what lead Myles to have the heart attack is unclear, what is clear is that Cowboys fans and players will mourn him.

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