Sessegnon was on Wearside over the weekend to discuss the details of a loan until the end of the season from French club Paris St Germain.
The 25-year-old met with chairman Niall Quinn and chief executive Steve Walton and the belief is that talks were positive and that a deal could be struck with PSG.
However, there is plenty of paperwork to be sorted and Sunderland do not feel a deal will go through in time for him to make his debut against Newcastle at the weekend.
The Benin international was the most likely candidate to join this week, so manager Steve Bruce is preparing his squad for the visit of their arch-rivals in expectation that there will be no new arrivals before the derby.
Bruce has also been looking to bring in Sulley Muntari from Inter Milan, although the chances of that happening now appear slim.
Muntari is keen to return to the Premier League after failing to make an impression at the San Siro, but he is reluctant to head for the Stadium of Light.
The former Portsmouth midfielder, who plays with John Mensah and Asamoah Gyan for Ghana, has expressed an intention to play in the south if he does head back to England.
Fulham and Tottenham, where he would rejoin former Portsmouth boss Harry Redknapp, are believed to be the front-runners for his signature.
Muntari is quoted as saying: If I have to leave Inter Milan, I'll go to London. That is the only possibility.
The addition of Muntari would have significantly boosted Bruce's midfield options, given David Meyler is facing months out with a knee problem.
Also, captain Lee Cattermole still not 100 per cent after his back problem, although there is a chance he will face Newcastle.
Sunderland, though, are unlikely to make major changes to personnel, unless there is a sudden sale of a couple of players that would increase the manager's transfer budget.
Bruce had shown tentative interest in Blackpool's Charlie Adam, but with the board at Bloomfield Road looking to receive nearer to £4m for a player with 18 months remaining on his contract, Sunderland are not pushing the situation.
Adam, Steve Sidwell and Sebastian Larsson have all caught Bruce's eye this month, but it would seem the cheaper option is to look at the foreign loan market which is where Sessegnon and Muntari fitted in.
Aston Villa have had an offer of £2.5m rejected for Adam, while Liverpool have been linked with an interest now that Kenny Dalglish has taken over.
But Sunderland, unless they suddenly find themselves receiving bids for players they would be willing to sell this month, are not in a position to invest in the squad until the summer.
Young Sunderland midfielder Liam Noble, meanwhile, has joined Carlisle on a month's loan. The 19-year-old could make his debut against Dave Penney's Bristol Rovers on Saturday.
He follows Michael Kay and Michael Liddle out on loan after they joined Tranmere and Gateshead respectively.