Head coach Lee Johnson is looking to add another striker to his squad and is also in the market for another attacking midfielder.
There is also a lack of options in centre midfield and cover at right-back due to long-term injury setbacks.
Johnson has said the club don’t have to sell players this month, yet the Black Cats are keen for their younger players to go out on loan to gain more game time.
Here are some of the deals which could happen between now and the end of the transfer window:
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1. Jermain Defoe (Free agent) - Potential in
A deal Sunderland fans would love to see happen. Defoe has spoken publicly about the option to return to Wearside, while League One rivals Oxford and Charlton are also thought to be interested. Still, Black Cats boss Lee Johnson has said a lot of things would have to happen for a deal to go through. Photo: Steve Welsh
2. Denver Hume - Potential out
Portsmouth are believed to be interested in the Sunderland left-back who has made just four league appearances this season. That is partly down to injury but Hume has also been second choice behind Dennis Cirkin at left-back. Sunderland would have to sign a replacement before letting Hume leave, though. Photo: JPI Media
3. Patrick Roberts (Manchester City) - Potential in
We have known about Sunderland’s interest in Roberts since the start of the month. Talks have progressed since then, though Roberts is still on loan at French club Troynes from Manchester City. That deal is expected to be ended which would allow the playmaker to move elsewhere. Photo: JPI Media
4. Arbenit Xhemajli - Potential out
The centre-back spent more than a year on the sidelines with a major knee injury so Sunderland have been careful with his recovery. Xhemajli has made just one senior appearance in the Papa John's Trophy this season so could be sent out on loan to gain more game time. Photo: JPI Media