It seems like we've been waiting forever for a legal decision that could not only transform football but also be linked to a single professional player. Finally, we might have a new Bosman. The verdict from the Court of Justice of the European Union (CJEU) on Friday, known as the Lassana Diarra ruling, is almost certain to bring about significant changes in the sport. This legal process, which began nine years ago, is still ongoing. Ultimately, it will be up to Belgian courts to decide whether key FIFA regulations concerning the transfer market are still valid. However, given that these final considerations must be made within the scope of EU law, and that the EU's top court has stated that FIFA's rules "go beyond what is necessary" in several respects, it seems likely that the current status quo may soon be a thing of the past.

On the surface, the case revolves around what happens when a player's contract is terminated "without just cause." This is what occurred with Diarra in 2014 when he was playing for Lokomotiv Moscow. A dispute over performance and wages led to his contract being canceled by the Russian club, with FIFA's Dispute Resolution Chamber (DRC) ruling against the former France midfielder and fining him. When Diarra subsequently signed with the Belgian club Charleroi, he was unable to complete the move because a transfer permit would not be granted until the fine was paid. Additionally, Charleroi would have been held liable for that debt if they had sought to finalize the deal, potentially facing punishment if they refused to pay it. The Belgian club decided they could not take that risk and thus abandoned the deal.

From this situation, the CJEU was asked to consider two key points: first, whether the refusal of a permit restricted Diarra's freedom of movement, and second, whether the obligations placed on Charleroi, and the potential for punishment, restricted their ability to compete. On both issues, the court ruled against FIFA. Even FIFA's defense that such rules were necessary to "ensure the regularity of sporting competitions" was deemed insufficient because the court found the rules "go beyond what is necessary to achieve that objective." FIFA now has one final opportunity to argue differently when it presents its case to the Belgian appeal court where this matter is being heard. The CJEU states that the plea will have to be convincing, arguing that "an exemption is possible only if it is demonstrated, by means of convincing arguments and evidence, that all the conditions required for that purpose are met."

The outcomes will not be immediate, but it seems that FIFA's initial response, that this ruling was insignificant and that "questions remained only over two paragraphs of two articles of the FIFA regulations," does not fully capture the potential scale of changes. It seems far more likely that players will be able to walk away from their contracts thanks to this ruling. It also seems likely that rules determining who is owed compensation and how much in the event of a "without just cause" breakup will have to change, as the CJEU states "such compensation criteria seem more intended to protect the financial interests of clubs than to ensure the supposed smooth running of sporting competitions." It also seems likely that the financial liabilities on buying clubs will change, too, away from an assumption that they are somehow responsible for the move, quite possibly to the opposite conclusion.

These are all substantial changes that are interconnected and will probably have unintended consequences, however they are resolved. But they are not the only things at stake for FIFA and other governing bodies as a result of this ruling. Dupont-Hissel, the legal firm representing Diarra, who just happened to also be Jean-Marc Bosman's lawyers, immediately responded to the verdict by saying it was a "total victory" for Diarra, affecting "all professional players" since 2001 and allowing them to "seek compensation for their losses," presumably those that came from being unable to terminate their contract and move to a club that paid them better. So, more legal action is on the horizon.

But more than that, there is renewed scrutiny on FIFA as a rule-maker. The Super League case last year led to an outcome whereby UEFA was told it had to be more accountable and its rule-making more transparent. That case is cited several times in the Diarra judgment, which could be seen as following on from it. Not only are questions raised here as to whether FIFA's rules are fair and their provisions proportionate, the judgment makes reference to the "uncertainty" or "lack of certainty" caused by the same rules, implying, at the very least, that they need to be rewritten for greater clarity. This, as it happens, aligns with the sentiment held by players' unions over a number of issues. Dupont-Hissel has been hired by FIFPRO, the global union, to represent it in a case it is bringing against FIFA over the upcoming Club World Cup, arguing the plans violate EU laws on workers' welfare. On Friday, the chief executive of the Professional Footballers' Association, Maheta Molango, himself a successful sports lawyer, said the Diarra ruling made a broader point, "demonstrating again that football cannot behave like it does not have to work within the same employment laws that apply to any other industry." Football authorities, Molango added, "need to be making an honest and open assessment of the suitability of their rules and how they sit alongside employment laws. They then need to start making genuine and proactive efforts to work with players and their unions."

Root and branch reform of the entire system of governance remains unlikely. But this ruling certainly makes it more possible, and it is hard not to conclude that it has the potential to alter the balance of power in professional football.