The Riders said Wednesday they have released Hughes after failing to sign him to a new contract.
“After ongoing negotiations that took place over the last several weeks, we were unable to come to an agreement with Charleston,” Jeremy O’Day, vice-president of football operations for the Riders, said in a statement.
“While we are disappointed, we want to thank Charleston for his dedication to the Riders and to the Saskatchewan community during his time with the club.”
Hughes signed with the Roughriders after being traded to the team by the Calgary Stampeders in February 2018.
In 34 regular-season games with the Riders, Hughes had 85 defensive tackles, 31 sacks, seven forced fumbles and scored two touchdowns.
He also appeared in two playoff games, making six tackles and one sack.
Hughes was an all-star in both seasons he played for the Riders, and was the team’s 2019 nominee for most outstanding defensive player.
Prior to joining the Riders, Hughes spent over 10 years with the Stampeders.
He won two Grey Cups with Calgary and holds the team’s all-time regular-season sack record with 99.
Hughes also had 372 defensive tackles, 38 special-teams tackles, three interceptions, 23 forced fumbles, five fumble recoveries and one touchdown as a Stampeder.