The club this morning announced the out-of-contract players who would either be kept on or let go this summer, with Brazilian Guly, who joined the club in 2010, representing the most high-profile departure.
The 32-year-old made 118 appearances during his time at St Mary's, scoring 23 goals.
Barnard and Forte, who had not played for Saints in the Premier League, have also been released.
Saints have offered new deals to youngsters Cody Cropper, Lloyd Isgrove, Sam McQueen, Omar Rowe and Jake Sinclair, all of whom were involved with the first-team at some stage during the most recent season.
Elsewhere, ten players from the club's development squad and academy have been let go.
They are Matt Young, Joe Curtis, Andy Robinson, Jamal Branker, Fraser Colmer, Corby Moore, Charlie Higgins, James White, Tom Leggett and Isaac Nehemie.