A number of recent crucial football matches have been won by the application of the kind of number-crunching that has already changed baseball — the Moneyball approach

Arsène Wenger, French manager of the London football club Arsenal, was looking in 2004 for an heir to the midfielder Patrick Vieira. He wanted a player who could cover lots of ground, so he scanned statistics from European leagues and spotted an unknown teenager at Olympique de Marseille, Mathieu Flamini, who was running 14km a game. But could he play football? Wenger went to look and signed him for peanuts. Flamini prospered at Arsenal before moving to AC Milan.

Back then, Wenger was one of the few in football who used data to inform his decisions. In a traditionally anti-intellectual sport, he was a keen mathematician with an economics degree. But now a data revolution is sweeping the sport. Most big European clubs now employ sophisticated number crunchers. Arsenal’s data department is led by a German with a background in investment banking.

Data-crunching computers began infiltrating most professions in the 1980s, but sport remained immune. The first to change was American baseball, which saw the rise of a subculture of nerdy statisticians who, in their free time, played with the numbers of their beloved sport. Their dean was Bill James, janitor in a Kansas factory, who in his typewritten, mimeographed Baseball Abstract tore apart the game’s traditional wisdoms. He proved statistically that traditional ploys like base-stealing made no sense.

Eventually, some inside professional baseball noticed the Jamesians. Billy Beane, general manager of the Oakland As, had been an intellectual baseball player who at 27 walked into the head office and said he wanted to quit playing and become a scout. Beane read James’s theories with fascination. He grew fed up with the “gut wisdom” of gnarled scouts, and hired a 20-something Harvard-educated statistician to find new players. Using new stats, the team identified undervalued talent. It turned out that baseball’s respect for natural athletes was misplaced. Fat men with good ball sense did just as well. “‘Big-boned’ is (...)