As the January transfer window heads towards its final 24 hours, Premier League clubs are facing a race against time to beat the deadline.

Here, Press Association Sport asks leading sports lawyer Daniel Geey for an insight into what is going on behind the scenes as players, agents and clubs alike all try to get the deal done.

At what stage of a transfer would you get involved?

By the time I am involved in a deal, almost always the commercial terms have been agreed – the wages, agents' commission fees and particular bonuses to be included, or clauses added in like around relegation or releasing a player. I tend to be provided the documents from the club, I usually act for the players and or agents in order to review them and make sure what has been agreed has been set out in the contract. My usual approach is to prefer not to be near training grounds or boardrooms so that I can review everything in the cold light of day in front of a screen in my office.

So there is plenty of reading to keep you busy?

There are almost two stages – one to get all of the documents signed in time, the second is the submission and registration process, with international transfers there is a FIFA element... work permits can need to be applied for or there might be image rights to deal with. The documentation is quite heavy and needs to be negotiated to a decent degree.

Does anyone still really use a fax machine?

I can't say I have sent a fax for a number of years! A lot of my informal communication and correspondence is all on WhatsApp and messaging. With a lot of my clients, if they are players, agents, individuals, generally the 'toing and froing', going back and forth on commercial terms is done instantaneously. That is the way the world is moving, which needs instant responses and makes sure everyone is available at the drop of a hat.

Is there ever a deal-breaker in the detail?

There is very few things in contracts which I see that I say is such a 'no no', that we can't necessarily do it. A lot of the time, so long as people are logical and rational in what I am asking with the requests I am making, then the other side will, on the whole, try to be accommodating, to understand the structure of how commission payments are made or the clauses, or something which was agreed in outline, then said in a different way in a contract... and you always want to try to protect your clients as much as possible.

I guess everyone is watching the clock?

It can be pressurised at times. Ultimately everybody knows that they are working for the same target if you are working for the player, the club or the agent. If you can get the deal sheet put in place, that gives us a bit more time, but it does really focus minds quite late in the day. Does a deal want to happen? Usually, it is yes.

Do any transfer deals really only kick off when we hear about it on deadline day?

Even when it is announced in the media that talks are going on, trying to get a deal sorted, it usually won't be they will have only been speaking for the last 10 minutes! A lot of the background will have happened in the days and weeks before it is being reported to being quite close to being done. It is very difficult for a player to wake up on deadline day, call his agent and say: 'I want to move, and to this club, on this day' and make sure everything aligns in enough time to be able to do the deal.

:: Daniel Geey is the author of Done Deal: An Insider's Guide to Football Contracts, Multi-Million Pound Transfers and Premier League Big Business, published by Bloomsbury Sport