And Sunderland have much work to do following the club’s retained list.
It was announced that Max Power, Grant Leadbitter, Josh Scowen and Callum McFadzean amongst others were set to leave the Stadium of Light.
Denver Hume and Luke O’Nien are weighing up contract offers whilst loanee Dion Sanderson has returned to Wolves.
That means Sunderland will likely look to strengthen in defence.
Here, we take a look at the free agent options available to Lee Johnson.
1. Sol Bamba
The popular defender has just been released from Cardiff City. At 36-years-old, Bamba is now in the twilight of his career but could potentially do a job in League One if he fancied one last hurrah.
Photo: Justin Setterfield
2. Shane Ferguson
The 29-year-old former Newcastle United man can play full-back and on the wing and has just left Championship club Millwall. The Northern Ireland international may have offers from clubs higher up the pyramid but presents an interesting thought for Sunderland nonetheless.
Photo: Jacques Feeney
3. Nathan Baker
At 30-years-old, Nathan Baker presents an interesting option to clubs. The defender has experience in the Premier League and Championship but has just been released by Bristol City. Interestingly, Lee Johnson worked with Baker during his time at Ashton Gate. Could a potential reunion be on the cards? As always, Sunderland will likely face competition from clubs higher up the leagues.
Photo: Michael Steele
4. Charlie Mulgrew
The former Celtic man spent last season on loan at Fleetwood Town but is now a free agent. The 35-year-old is attracting interest from clubs north of the border, however, and he may be slightly too old for the model Sunderland's new owners are trying to implement at the Stadium of Light.
Photo: Pete Norton