ON JULY 13TH Chelsea, a team in the English Premier League, put three goals past Paris Saint-Germain (PSG), of France’s Ligue 1, to win the Club World Cup. As well as earning bragging rights—PSG were the tournament favourites—and a gargantuan gold trophy, Chelsea will take home around $110m.

They will be grateful for the payday. Eagle-eyed observers may have noticed that the front of Chelsea’s shirt is blank. Since an American consortium bought the club in 2022, the owners have been searching for a lucrative sponsorship deal, with mixed success. Chelsea’s peers, meanwhile, are flush with cash: PSG are reportedly paid around $70m a year by Qatar Airways. (Both club and sponsor are owned by the Qatari government.)

For Joey D’Urso, a journalist at the Times, such details matter. In “More Than A Shirt” he argues that football jerseys—and especially the brand names that appear on them—can tell you a lot about economics and geopolitics. Football’s governing bodies have excelled at commercialising the sport, he argues, but failed to protect it from questionable ventures.

A generation ago, shirt sponsorship was simpler than the offside rule. Consumer goods companies paid clubs for the chance to reach local fans. At the start of the Premier League era in 1992, Liverpool was sponsored by a beer brand and Arsenal by an electronics company. But as football became more popular globally, the shirts of the most successful teams attracted a broader array of sponsors.

Mr D’Urso describes a deal made in 2006 when a top-flight German team, FC Schalke 04, switched their main sponsor from a local insurance firm to Gazprom, a Russian gas producer. This lucrative deal was a departure from the norm, for “Nobody watching…is going to go out and buy a cubic metre of Gazprom gas,” the author notes. Instead, an energy expert says, Gazprom sought out Schalke to improve Russia’s image as “the friendly neighbour”. It worked. During the course of the deal, an increasing share of German’s energy mix was given over to Russian natural gas.

The book’s strongest material shows how some leading clubs have accepted sponsorship money without doing their due diligence. In 2021 Chelsea signed a deal with Leyu Sports, an Asian gambling firm. Players were corralled into speaking Chinese in promotional videos and the company’s logo was displayed at the team’s ground. But when Mr D’Urso tried to track down the firm that claimed to have brokered the deal, he could not prove its existence. Pictures of its employees were stock photos. “Simply put,” he concludes, “nobody has any idea who is running these companies.” Without this information, teams do not know what they are promoting, even if they are practising “ignorance rather than intentional deceit”.

Football has embraced crypto schemes with a similar lack of scrutiny. In 2021-22, all but one of the 20 Premier League clubs advertised a crypto product to their fans. These clubs collaborated with crypto startups to create non-fungible tokens that were intended to be collectables. Mr D’Urso learns that the crypto industry locked onto football because it realised it was “the cheapest way of advertising to young men”, a cohort who are more inclined to take financial risks. Prices soon crashed (though crypto has since rebounded).

Mr D’Urso speaks to angry and embarrassed fans. In the absence of sufficient regulation, some believe they have been exploited by their clubs. Others are surprised that players they considered “legit” would endorse such risky schemes.

A few feel obliged to give sponsors a kicking. Earlier this year Arsenal fans called for the club to end its agreement with Rwanda’s tourism board (see picture) after a government-backed rebel group invaded eastern Congo. (The countries have since signed a shaky truce.) Mr D’Urso argues that few, if any, supporters want “to wrestle with complex geopolitical issues”. Yet “More Than A Shirt” shows why geopolitics keeps invading the pitch.