(From left to right) Enzo Fernandez, Jude Bellingham and Moises Caicedo are being chased in the transfer market
The January transfer window has produced several surprises - and there is still time for Premier League clubs to do some business.
Here is everything you need to know before transfer deadline day.
- Transfer gossip - what the papers are sayingFind all the latest football transfers on our dedicated page
When does the transfer window close?
The transfer window opened on 1 January and will close at 23:00 GMT on Tuesday, 31 January for the Premier League.
New signings are eligible for the next Premier League game if the club submit the required documents by midday on the last working day before that match.
In Scotland, the window shuts at 23:59 GMT on 31 January, while the Women's Super League closes at midnight for international transfers and 17:00 for domestic deals.
Elsewhere in Europe, the Bundesliga shuts at 17:00, Serie A at 19:00, La Liga at 23:00 and Ligue 1 at 11:59 - all on 31 January.
Who could be on the move? Borussia Dortmund midfielder Jude Bellingham impressed for England at the World Cup in Qatar
Chelsea are reportedly still trying to sign Benfica and Argentina midfielder Enzo Fernandez despite having bids rejected at the start of the month.
The Blues may also return with an improved bid for Brighton and Ecuador midfielder Moises Caicedo.
Borussia Dortmund and England midfielder Jude Bellingham is attracting lots of interest with clubs including Liverpool, Manchester City and Real Madrid said to be fighting for his signature.
Everton winger Anthony Gordonexternal-link could attract attention from Newcastle, while Brighton are reportedly interested in £20m-rated Shakhtar Donetsk and Ukraine centre-back Mykola Matviyenkoexternal-link.
Bournemouth are said to be vying with Southampton for the signature of Villarreal and Senegal forward Nicolas Jacksonexternal-link.
What deals have already happened?Cristiano Ronaldo is reportedly receiving the biggest football salary in history at more than £177m per year
Following a controversial exit from Manchester United, Cristiano Ronaldo completed a move to Saudi Arabian club Al Nassr.
Chelsea have made six signings including Shakhtar Donetsk forward Mykhailo Mudryk for a fee rising to £89m, PSV Eindhoven winger Noni Madueke for £30m, Monaco defender Benoit Badiashile for £35m and Joao Felix on loan from Atletico Madrid.
League leaders Arsenal wrapped up the signing of Brighton midfielder Leandro Trossard for £21m and added defender Jakub Kiwior from Serie A club Spezia for £17.6m.
Leeds signed Hoffenheim forward Georginio Rutter for a club record fee of £36m, and Liverpool brought in Netherlands forward Cody Gakpo from PSV Eindhoven in a deal which could rise to £45m.
Elsewhere, Aston Villa signed striker Jhon Duran for £18m from Chicago Fire, Danny Ings moved from Villa to West Ham for £12m and Leicester signed Copenhagen defender Victor Kristiansen for £17m.
Bournemouth recruited winger Dango Ouattara for about £20m from French club Lorient, and Southampton bought midfielder Carlos Alcaraz from Argentine side Racing Club for £12m.
Wolves signed Paris St-Germain winger Pablo Sarabia for £4.4m, Nottingham Forest landed Palmeiras midfielder Danilo for about £16m and Aston Villa completed a £13.2m deal for Real Betis left-back Alex Moreno.
Meanwhile, striker Chris Wood moved from Newcastle to Nottingham Forest on loan, and Burnley's Wout Weghorst was loaned to Manchester United.
- Kiwior: From doughnut lunches to Arsenal moveHow Gakpo has gone the extra mile for successWho is Chelsea's new big-money signing Mudryk?
How much has been spent so far?Chelsea signed Mykhailo Mudryk for a fee rising to £89m on an eight-and-a-half-year contract
More than £437m has already been spent in this transfer window by Premier League clubs.
Chelsea's six signings have cost about £181m - including the £89m transfer of Mudryk - while Leeds have broken their club record for the £36m paid to Hoffenheim for forward Rutter.
Gakpo's move to Liverpool was worth £35.4m-£44.3m, and PSV Eindhoven said it was a record transfer fee received by them.
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