The transfer window for Premier League and Championship clubs slammed shut yesterday, with the League One and Two deadline remaining open until September with Jack Ross in the market for a left-back.
Meaning Sunderland could target players from clubs who need to offload fringe players.
Scroll down and click through the pages to see the options available:
1. Danny Fox - Wigan Athletic
The 33-year-old veteran featured sporadically for the Latics last season. Reaching the twilight of his career, Fox may be eager to start games and Wigan have several left-back options.
Photo: Stephen Pond
2. Sylvain Deslandes - Wolves
The 22-year-old France under-20 international is unlikely to break through at Premier League Wolves - meaning the left-back is likely seeking another loan move.
Photo: Jan Kruger
3. Cameron Borthwick-Jackson - free agent
The ex-Manchester United man is a free agent and was last seen training with Sunderland's pre-season opponents Heerenveen. However, that arrangement has now ended.
Photo: Matthew Peters
4. Joe Mattock - Rotherham United
Mattock will be regarded as one of League One's better left-backs after coming down from the Championship last season. Sunderland may have to pay a sizeable fee should they wish to land him.
Photo: Nigel Roddis