This could be an extraordinarily busy day for Brighton.
The Seagulls, having already sold Ben White this window, are financially strong enough to hold on to their best players but that is unlikely to stop clubs testing their resolve for some star players.
Meanwhile, there could yet be a new face or two coming through to doors of the Amex before the window shuts. Graham Potter knows where he needs to strengthen and there are three big deals that could happen.
Deadline day always brings with it a number of surprising last-minute deals that may or may not go through but there is already plenty of speculation that has been doing the rounds for days or even weeks and, in some cases, months.
Elsewhere, Liverpool may yet bolster their squad by swooping for a player from a Premier League rival. For Everton, Rafa Benitez looks set to be active in the last few hours of the window as he bids to bolster his squad and build on an impressive start to the season.
The London clubs, particularly West Ham, could be busy – there looks to be work to do at Arsenal.
Cristiano Ronaldo’s headline grabbing return to Manchester United could mean more than one player heads for the exit door at Old Trafford.
Take a look below and flick through at some of the big deals that could be set to go through before the 11pm deadline.
1. Adama Traore - Spurs
The Wolves star is said to be desperate to push through a move to London and join up with former boss Nuno Espirito Santo with "super-agent" Jorge Mendes doing everything he can to facilitate a deal.
Photo: Jack Thomas - WWFC
2. Callum Hudson-Odoi - Borussia Dortmund
The 20-year old's future is unclear, Dortmund are said to be "very keen" on a loan deal but Chelsea are on record as not wanting to let the England international leave. Hudson-Odi himself, understandably, wants to play first team football.
Photo: Visionhaus
3. Connor Roberts - Burnley
Burnley were first linked with the Welsh international back in June but have only now opened talks with the defender and could push to get a deal over the line
Photo: Eurasia Sport Images
4. Alex Oxlade-Chamberlain - Southampton
The Ox never seems to be short of Premier League suitors whenever a transfer window opens and this time it's the Saints who are favourites to land his signature. Ralph Hasenhüttl is keen on a loan deal for the midfielder but plenty other clubs are rumoured to be in the market including Crystal Palace and Newcastle.
Photo: John Powell