But which former Black Cats stars are now free agents having been released by clubs and which players will see their deals expire soon?
Here, we take you through all of the ex-Sunderland players who have been released or are soon to be released.
Are there any realistic targets that the Black Cats could look to re-sign?
Scroll down to take a look at the list:
1. Patrick van Aanholt
Barcelona are reportedly considering a Bosman move for 30-year-old former Sunderland defender Patrick van Aanholt, who is set to leave Crystal Palace when is contract expires at the end of the season. Photo: Pool
2. Stewart Downing
Stewart Downing enjoyed a loan spell at Sunderland during the 2003/04 season. Following spells with Aston Villa, Liverpool, West Ham and Middlesbrough; the attacker is now a free agent after departing Championship club Blackburn Rovers. Photo: Alex Pantling
3. Martyn Waghorn o
South Shields-born striker Martyn Waghorn came up through Sunderland's academy but has just left Wayne Rooney's Derby County after three seasons at the club. Photo: Alex Pantling
4. Jimmy Dunne
Jimmy Dunne is out of contract at Burnley at the end of the season having spent time one loan on Wearside under Jack Ross. The 23-year-old is out of contract in the summer and no deal has yet been agreed to extend his Turf Moor stay. Photo: Naomi Baker