So with Phil Parkinson likely already looking towards the summer transfer window – whenever that may be – we take a look at the players in League One who could improve the Black Cats next season.
We’ve picked one from every club, but have we missed anyone out? Let us know by tweeting @sunechosafc.
Scroll down and click through the pages to see our picks:
1. Accrington Stanley - Jordan Clark
It's something of a surprise that none of the League One 'big boys' have snapped-up Clark yet, given his consistently strong performances at the Wham Stadium. Expect some interest in him during the summer. Photo: Jan Kruger
2. AFC Wimbledon - Callum Reilly
While Wimbledon have been inconsistent as a team, defensive midfielder Reilly has proved a reliable recruit - and could fit seamlessly into Parkinson's system. Photo: Paul Harding
3. Blackpool - Armand Gnanduillet
No surprises from the Seasiders. Sunderland need a goalscorer, and Gnanduillet has proven he can regularly find the net in League One. He'd a popular addition among supporters for sure. Photo: Nathan Stirk
4. Bolton Wanderers - Harry Brockbank
The young defender was linked with Sunderland last summer, and could yet be a target in the coming months. Phil Parkinson will know him well, and could be looking to bolster his defensive options in the summer - with the likes of Joel Lynch, Tom Flanagan and Alim Ozturk out of contract. Photo: Gareth Copley