Chelsea's appeal against their two-window transfer ban will be heard this week. Here are all the details about what happens next.
Why were Chelsea given a transfer ban?
FIFA handed down a two-window transfer ban to Chelsea in February, meaning they were unable to sign any new players in the summer transfer window, and will not be able to bring in anyone from another club in January either.
The game's world governing body found Chelsea guilty of breaching two of its regulations on player transfers, specifically regarding bringing in U18s and 'third-party influence'.
Chelsea were found to have committed 150 breaches concerning almost 70 academy players, including claiming they were trialists and had not played in official games for the club's youth sides - but one was found to have participated in 75 games across a three-year period.
The club also had their first appeal thrown out by FIFA's appeal committee in April, when it was criticised for "inexcusable" breaches of the regulations.
How come Chelsea signed Mateo Kovacic and Christian Pulisic in the summer?
Technically, Chelsea's transfer ban is a ban on 'registering' new players. Pulisic was signed in January 2019, but loaned back to Borussia Dortmund for the rest of 2018/19.
Kovacic had only been on loan at Chelsea from Real Madrid, but because he was already registered with the club, they were able to make his move into a permanent one during the summer transfer window.
What's happening now?
Chelsea have gone to the Court of Arbitration in Sport (CAS), a multi-national court used to judge on contentious issues.
That new appeal will begin in Switzerland on Wednesday, with both the club and FIFA set to make submissions about the case during the hearing.
What happens next?
A decision is not expected immediately on whether Chelsea's ban is reduced, but it is thought it should come in time for Chelsea to prepare for the January transfer window - if they are going to be allowed to participate.
The club has been linked with a number of players in anticipation of any potential redemption, but will not be able to bring in any new additions until the summer unless CAS rules in their favour.
Follow the January transfer window on Sky Sports
As we approach January, the transfer rumour mill is already hotting up - for Chelsea as much as anyone else.
Keep up with what's happening across the Premier League and beyond on skysports.com, through our Transfer Centre blog providing the latest news and rumours on comings and goings 365 days a year.
There's also a range of further coverage and club-by-club updates to make sure you don't miss out on any transfer talk ahead of the window opening on January 1.