Sunderland manager Jack Ross has said players will have to leave the club before any new signings can be made.
The Black Cats have only added two players to their squad this summer, bringing in both right-back Conor McLaughlin and goalkeeper Lee Burge on free transfers.
Ross will likely have wanted to make improvements to his squad in the transfer window after he came tantalisingly close to leading them to promotion last season.
Sunderland suffered a last-minute defeat to Charlton in the League One play-off final.
Speaking to Chronicle Live, Ross said that for new players to be brought in, current squad members would have to leave.
He explained: "In terms of where we are squad wise, with numbers we’re a lot healthier than we were this time last season.
"We have enough numbers in the group to satisfy a lot of positions.
"However, as always, we're always looking to improve the quality. It's not easy because we've got good players at the club already, but we've worked hard to identify those that have the quality and fit within the structure of the club now.
"The reality at the moment is that we're in a position where in order to bring ones in, we need to move ones on.
"That's not always easy to do, so I'm satisfied with what we've got at the moment, but looking to improve if the right player not just becomes available but fits the structure of the club."
The Verdict
It will be scary for Sunderland fans to hear that there is a chance the club will not make any further signings this summer.
Ross should be keen to make some more additions to his squad after they fell short of promotion last season and it appears that won't happen unless players leave the Stadium of Light.
The Black Cats finished fifth last season and kept five fewer clean sheets than any of the promoted sides in the 2018/19 campaign, so he may be looking to solidify his defence.
No striker other than Josh Maja, who left the club in January, scored more than five goals for Ross last season and the Scotsman could feel he needs more reinforcements up front.