It has been 15 years since sabermetrics, the empirical analysis of baseball, was popularized by Michael Lewis’ bestseller Moneyball: The Art of Winning an Unfair Game, marking the beginning of Major League Baseball’s (MLB) data revolution. Today all teams in the league use it, but only Jeff Luhnow was able to turn a failing franchise into World Series Champions by going all-in on sabermetrics. What did he do differently? He combined quantitative analysis with active management.

With no baseball experience, Luhnow left his job as a McKinsey consultant to work for the St. Louis Cardinals at the beginning of the “Moneyball revolution.” After a couple of championships with the Cardinals, he was named general manager (GM) of the Houston Astros – and he turned that battered franchise into the 2017 World Series champions.

Luhnow spoke at the Wall Street Journal’s Future of Everything Festival on May 8 about how data wins championships.

He was proudly wearing an Astros World Series ring that is covered by so many diamonds it wouldn’t look out of place in a Kardashian lineup. Luhnow explained that it tells the whole story of the team’s turnaround. With 56 diamonds at the top representing the number of years the Astros were in existence until they won their first championship and 11 diamonds representing the team’s postseason wins against – the ring would clearly impede his ability to swing the bat.

I will review how Luhnow successfully rebuilt the Astros using an active management approach to sabermetrics, but first let’s look at how he ended up in baseball.

How did Luhnow end up working in baseball?

“I had three careers before I got into baseball,” Luhnow said. He had a quantitative background, working as an engineer. He went to business school and worked for McKinsey for six years. Then he worked for two high-tech startups as a senior executive.

“At no point did I think I was going to get into baseball,” Luhnow admitted. “But the opportunity came to me in 2003, and I joined the St. Louis Cardinals.”