While money in football has only ever been going up, in recent years there has been a significant boom, with the emergence of State-backed football clubs like PSG and Man City, and sponsorship and television deals that have seen the old guard reach revenue previously unthinkable.

This has been reflected in the transfer market, with astonishingly high fees changing hands — none more startling than the transfer of Neymar from Barcelona to PSG last summer. Even Barcelona, whose revenue stream quadrupled in a just a decade, couldn’t foresee the rise of the market as they set what they deemed a prohibitively high release clause in Neymar’s 2016 contract extension — €222m. They were wrong.

It’s over twenty years since the Bosman ruling changed football, handing more power to players and fostering the rise of the super-agent as players were able to negotiate their own transfers at the end of a contract. The transfers of Steve McManaman, Patrick Kluivert and most famously Sol Campbell all demonstrated the impact.

Now, as money in the game has hit unseen heights, there are new implications of the Bosman rule.

Alexis Sanchez, who is free to leave Arsenal in the summer, is reportedly to earn a record amount. The exact figures may not be confirmed, but regardless he looks set to be the highest paid player at Manchester United, and in the Premier League, as well as a receiving substantial signing fee for himself and his agent.

This would almost certainly not be the case if Sanchez was still contracted to Arsenal and Manchester United were forced to pay the market rate for him — upwards of £50m. In the absence of such a fee — instead, offloading a player deemed surplus by Jose Mourinho — the bargaining position of the player’s camp is strengthened. Financially, (almost) seeing out his contract at Arsenal has been extremely beneficial for Sanchez and his agent, Fernando Ferlicevich.

Arsene Wenger has predicted a new precedent. Unless the market crashes, this move could well become a blueprint for players (or more pertinently, their agents) in the coming years.

“In the future, you will see that more and more, players going to the end of a contract. Why? Because transfer [fees] become so high, even for normal players, no one will want to pay the amount of money that is demanded. I’m convinced that in the next 10 years it will become usual.” — Arsene Wenger

Take a hypothetical example — Kylian Mbappe. If his career trajectory continues as expected, he will be established as one of the best players in world football (if he’s not already). When he officially becomes a PSG player, he will be contracted to 2022, at which point he will be 23 — years and years still ahead of him. Should he see out the contract, his bargaining position would be unprecedented. It’s impossible to predict what the market will look like, but let’s say he’s a €300m player, available for free. The demands that his camp could make in those circumstances are extraordinary— especially if they’re willing to listen to offers and court clubs to compete for a signature.

This raises the question of what clubs can do to stop this from happening — which is to say, bend to the same demands as any new courters. Take a look at Lionel Messi. Barcelona, last summer’s crisis club — with a board under considerable pressure — simply could not afford to let the best player in the world leave. Messi’s camp knew it. Leaks have shown his latest contract dwarfs any in the history of the sport — reportedly worth over €100m per year and with a loyalty bonus of €70m.

Contrast this with his eternal rival, Cristiano Ronaldo.

He signed his last contract extension in November 2016, at €365,000 a week — at the time, this made him the highest paid player in the world. However, the market has developed rapidly since then — seeing three players break the €100m mark for a transfer. Now, Neymar’s earnings far exceed Ronaldo’s, and he earns just a fraction of what Messi does. For the current Balon D’or holder, an exceptionally self-regarding footballer, this will sting.

As a now bi-annual tradition, his camp has put out stories about he may leave Real Madrid. However, his bargaining position is extremely weak. His current contracts runs until 2021, at which point he will be 36. It doesn’t appear that any club is actually in for him. Why on earth would Madrid give him more money now?

In hindsight, it may have been a mistake to sign the latest contract when he did — Jorge Mendes camp are paying the price for not having the foresight of how the market would go. If he did as Messi did, waited until the threat of leaving was realistic (his last contract was also due to expire in Summer 2018), he may have been able to force the club’s hand.