How could football – the “world game” – face a sustainability issue at the highest level? The question is raised by French club Paris Saint-Germain’s signing of Lionel Messi, one of the greatest players ever, on a reported annual salary of US$101 million, plus a sign-on fee of US$47 million. Even more grotesque in normal terms, it represents a bargain in that his former club Barcelona was paying the now 34-year-old a reported US$220 million a season. After years of uninhibited spending on top players, such out-of-this-world figures can be contemplated only by an increasingly small number of clubs, typically backed by oligarchs or in this case a nation state. PSG is owned by an investment trust financed by the government of Qatar, host of next year’s World Cup. Messi is not an isolated example. The much less well-known Jack Grealish, 25, has become the most expensive player in English Premier League history with a US$138 million deal to join Manchester City from Aston Villa, quickly followed by Romelu Lukaku’s return to Chelsea from Inter Milan for a reported club record fee of US$135 million. The Messi saga highlights the question of where it will all end. Many clubs in the top leagues are struggling. The Spanish football authorities are cracking down on inflated wages for players. In a bid to keep him at his boyhood club of 20 odd years, Barcelona and Messi agreed on a big pay cut. But even this was rejected by the authorities, so he went. Another dimension of the inflation is that PSG can expect to get its money back and more, given that Messi is said to have brought in US$376 million more than he cost Barcelona over the last four years through merchandising and sponsorships. Many football clubs have run into trouble during the pandemic. There have been some big transfers but most have more limited resources. Yet the salaries of top players remain extraordinarily high. One reason for the ill-fated attempt to form a super league in Europe was so the top clubs could get television revenue rights. It all comes back to the issue of financial sustainability. Football’s wealth gap can tilt the playing field with scant regard for most fans’ club loyalty. For their sake and the game’s future health, football must find a way to sustain itself, not just for the big clubs but for all the others.