Middlesbrough have allowed experienced duo Stuart Parnaby and Frazer Richardson to leave the Championship club.
Parnaby returned to the club in 2012, but after making just three appearances for the North-East team last season, he has been released at the end of his two-year deal.
Full-back Richardson, who featured just once after the arrival of head coach Aitor Karanka in November, spent the final months of the season on loan at Ipswich Town.
Goalkeeper Jayson Leutwiler, defenders Lewis Sirrell and Birger Meling, and midfielders Jake Fowler, Cameron Park and Matthew Waters have also been informed that they are free to leave the Riverside Stadium.
