John Coppolella was never much of an athlete. He’d been the manager of Notre Dame’s football team. But Coppolella loved baseball, loved it so much that he turned down a six-figure job at Intel to earn barely a subsistence wage as a Yankees go-fer. His parents were not pleased.

Coppolella’s heroes were never ballplayers. His heroes were executives, two of whom he’d come to work under – John Schuerholz, who hired him away from the Yankees, and John Hart, who’d become his mentor. By his 36th birthday, the guy with the economics degree from Notre Dame was the general manager of a big-league club and the de facto author of the most aggressive rebuild the sport had ever seen. He mightn’t have fit the profile, but by golly he’d gotten where he wanted to go and was, damn the torpedoes, doing as he wanted to do.

On Monday, it all went away. Coppolella resigned as the Braves’ GM for what the team described as “a breach of Major League Baseball rules involving the international player market.” With the first full wave of this rebuild poised to hit SunTrust Park next season, the rebuilder-in-chief is out.

The international player market is a murky place. (Scout Gordon Blakeley, an old pro on the international scene, also resigned Monday.) Everyone had the Venezuelan teenager Kevin Maitan ticketed to sign with the Braves long before he was eligible to sign with any team; sure enough, Maitan signed with the Braves in July 2016 and is regarded, at age 17, as one of the 10 best prospects in what has become the sport’s No. 1 farm system. That farm system would never have gone from fallow to bountiful without some serious pushing. Monday’s resignation suggests that Coppolella pushed too hard.

Even when he was a front-office guy without a seat at the grown-up table, that was his M.O. He’d come to work with an exotic trade proposal, only to be shot down by a higher-up. He’d come back after lunch and say, “What if we do this instead?” He was relentless, and there were some who considered him too much. A year ago, Hart – who has nurtured many of the best and brightest in the sport – said: “The most valuable asset I’ve been fortunate to have is John Coppolella, with his work ethic and creativity.”

Without Coppolella’s manic intensity, the Braves would never have collected so many prospects so fast. But manic intensity can bear a cost: The Hector Olivera trade was always a reach, and in hindsight the Andrelton Simmons deal seems the work of a young GM desperate to make his mark. And yet: Not a month after trading Simmons, Coppolella swung the Miller-for-Swanson/Inciarte/Blair trade, which many consider the best deal of this century.

When you move this fast, you make enemies. Some baseball folks weren’t crazy about the nerdy non-athlete, whose ingenuity was widely hailed among the sabermetric set (read: nerds). Still, that No. 1 farm system had to come from somewhere. Largely it was the work of Coppolella, who was as smart as all get-out and backed by Hart and Schuerholz and Bobby Cox. To be nearer the Braves’ new ballpark, Coppolella had moved his wife and three young children from Newnan to East Cobb. He’d gotten the job he’d wanted, and he was within a year or two of reaping the rewards. Then he resigned.

Jeff Passan of Yahoo! Sports tweeted Monday: "MLB was looking into everything from Braves' international operations to its domestic draft to Coppolella's treatment of Braves employees." He also tweeted: "Early on in investigation, little evidence had been found to corroborate a number of accusations levied against Coppolella."

It’s unlikely that mere vocational jealousy would have forced this resignation. (Contacted via text message Monday, Coppolella declined to comment.) And it’s a matter of record that the Braves played the draft-slotting game as hard as anyone, spending all but $5 of their 2016 allotment. Asked what the Braves did with that fiver, Coppolella said: “We split a hamburger.”

This rebuild wasn't going to work by taking half-measures, which fed into Coppolella's wheelhouse. He was pedal-to-the-metal 24-7. He once said, "The first thing I think about when I wake up is the Atlanta Braves." At his first press conference as fully minted GM, he said his aim – forget making the playoffs – was "to bring a world championship to the city of Atlanta." The final sentence of an essay written by this correspondent for the 2016 Baseball Prospectus yearbook: "He might be new to the job, but he is not afraid."

He wasn’t a politician, wasn’t an old-time baseball hand. He was an economics major who loved the game. John Coppolella had the job of his dreams and was doing it the way he’d envisioned. Now he’s gone. And several dozen baseball execs are lusting to inherit what he built.