AFP Sport looks at five of the clubs likely to be busiest before the window closes on February 2:

Liverpool to splash out again

The Reds spent more than any Premier League side ever has in one window just a few months ago, splurging nearly £450 million ($606 million) on six new additions.

However, there has been little return on that investment and injuries look set to force the English champions back into the market.

Alexander Isak's British record £125 million move from Newcastle headlined Liverpool's summer spending spree, but the Swede is set for at least two months on the sidelines with a broken leg.

Despite splashing out around £300 million on forwards in the summer window, Arne Slot's attacking options are currently threadbare with Mohamed Salah also absent at the Africa Cup of Nations.

Salah's future remains uncertain following his public outburst at being dropped by Slot and should the Egyptian depart, Liverpool will be in the market for a replacement.

Hampered by financial sustainability rules, Villa were unable to spend freely in the summer

Can Villa bolster title challenge?

Villa's dreams of maintaining a challenge against the might of Arsenal and Manchester City in the title race will depend on what they can do over the next month to strengthen Unai Emery's squad.

Hampered by financial sustainability rules, Villa were unable to spend freely in the summer. Yet Emery performed miracles to inspire an 11-game winning run in all competitions prior to Tuesday's 4-1 defeat at Arsenal.

Despite limited headroom, the Villa hierarchy managed to significantly improve the side in the January window 12 months ago when the loan signings of Marcus Rashford and Marco Asensio nearly fired them into the Champions League.

Semenyo set for City

Pep Guardiola's men look to have won the first major transfer battle of the month in securing Antoine Semenyo from Bournemouth. The Ghana forward has also attracted interest from Liverpool, Chelsea and Tottenham after scoring nine times in the Premier League this season.

Semenyo has a reported £65 million buyout clause in his contract, but that must be activated before January 10. City are not hanging about as they aim to add extra firepower to what is already the highest scoring side in the Premier League.

However, goals from wide positions have been a problem for Guardiola. Jeremy Doku, Savinho, Oscar Bobb and Omar Marmoush have just one Premier League goal between them so far this season.

Mainoo on the move?

Manchester United's January business is likely to be determined by the future of Kobbie Mainoo. The England international, who shone in the Three Lions' run to the Euro 2024 final, is yet to start a Premier League game this season.

Ruben Amorim does not appear to see Mainoo as compatible with captain Bruno Fernandes and both have been injured in recent weeks to severely limit United's midfield options.

Bryan Mbeumo and Amad Diallo are also away at the Africa Cup of Nations, but Amorim is cautious of recruiting for the short-term.

"If we are not sure, if everyone is not aligned, it's better not to bring anyone and to work with the players that we have," said the Portuguese coach. "We cannot do the same mistakes that we did in the past."

A sale of Mainoo, who was a product of the United academy, would significantly help United's wiggle room under financial sustainability rules to add another midfielder.

West Ham are starring down the barrel of dropping out of the Premier League for the first time in 14 years

West Ham's rescue mission

West Ham are starring down the barrel of dropping out of the Premier League for the first time in 14 years. The Hammers are four points adrift of safety but are also chasing other sides on the up in Nottingham Forest and Leeds.

A striker appears the top order of business for Nuno Espirito Santo with Niclas Fuellkrug already having departed to join AC Milan on loan.

K. Mainoo

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