Baseball is a game of numbers. It always has been — and for some fans, players and managers alike, the data become an obsession.

But the obsession appears to have gone too far this time. The FBI is investigating an allegation that employees in the St. Louis Cardinals front office illegally hacked into a computer database of a rival team, the Houston Astros.

Investigators have uncovered evidence that Cardinals personnel broke into an Astros internal network and a special database the team had built. The hack compromised information about trades, proprietary statistics, scouting reports and medical assessments.

The hacking didn’t gain much of a competitive edge. The Cardinals already have the best record in the Major Leagues, six games ahead of the Pittsburgh Pirates in the National League’s Central Division. For that matter, Houston isn’t even a National League team. The Astros and Cardinals play only sporadically.

Instead, vengeance was the apparent motive — an attempt to gum up the works of Jeff Luhnow, the Astros’ general manager, who until 2011 had been a successful executive with the Cardinals.

Luhnow is a numbers guy, no question about that. One of the foremost minds in the data-driven “Moneyball” phenomenon, Luhnow built an extensive and successful minor league system for the Cardinals.

Now he’s doing the same for the Astros — and that apparently angered some of the administrative staff he left behind in St. Louis, the investigators say.

Part of the irony behind the emerging scandal is that the most influential baseball mind of the 20th century, Branch Rickey, was the original numbers guy — as the general manager of the Cardinals from 1919 to 1942.

Rickey was the Jeff Luhnow of his day — the first GM to track every hit, run and out of every player on his team. He hired individuals to track and record the direction and distance of every hit. He is widely regarded as one of the pioneers in the statistical analysis of baseball, what’s now known as sabermetrics — or moneyball — being practiced by the likes of Luhnow.

Rickey later was GM for the Brooklyn Dodgers and Pittsburgh Pirates. He’s best remembered for signing Jackie Robinson to break professional baseball’s color barrier.

A devout Methodist, Rickey championed a style of play that was aggressive but fair — push the rules to their limit without breaking them.

The best of our national pastime’s heritage is traced to this remarkable man and his work with the St. Louis Cardinals. That makes this scandal involving the Cardinals all the more regrettable.