The Tangerines are unlikely to delve into the market, but have the option of signing free agents outside the window should they require any additional depth or cover.
But which players are available as free agents? We take a look at some of the exciting options that Simon Grayson could yet pursue should he wish to seek new recruits:
7. BEN ALNWICK
Phil Parkinson revealed that Alnwick was training with the Black Cats after leaving Bolton Wanderers. Whether he remains there is unknown, but the stopper could prove an option if Sunderland need to dip into the market.
8. ROSS McCORMACK
A target for Sunderland in their Championship days, McCormack remains a free agent. His wage demands could well prove a stumbling block for any League One side aiming to sign him, though.
9. BRADLEY WRIGHT-PHILLIPS
Largely unproven in the English leagues, Wright-Phillips has an eye-catching record in the MLS - and is now a free agent after leaving New York Red Bulls. Could a return to home shores prove appealing?
10. BREK SHEA
Injury has hampered the development of the former USA international but, fresh from a spell with Atlanta United, Shea is ready to work his way back into the game.