Chicago Cubs President of Baseball Operations Theo Epstein is only 46 years old, but his place in the Baseball Hall of Fame in Cooperstown is secure. In fact, one could make a strong argument that he's the greatest general manager and team builder in major league history.

In 2002, the Yale University graduate became the youngest general manager in MLB history — just 28 years old — when he was hired by the Boston Red Sox to run the front office. Just two years later, he ended the iconic franchise's 86-year curse. After winning a second World Series with Boston in 2007, Epstein resigned and subsequently became the Cubs' President of Baseball Operations. In 2016, he put an end to yet another curse, one that dated back an almost unfathomable 108 years.

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In addition to brilliant trades and shrewd free agent signings, Epstein has built three World Series clubs on the back of keen drafting and scouting. When selecting and observing players, the executive looks at much more than just arm strength, bat speed, power, and smooth hands. Temperament, and the ability to face and overcome obstacles, are significant factors.

"We won't even consider drafting a kid unless the scout can present to us, in writing, three examples of when the player faced and overcame adversity on the field [and] off the field," Epstein told Spartan CEO and founder Joe De Sena on the Spartan Up! Podcast.

Epstein's words are gospel not only because of the wins he's accumulated, but also because of the roster of draftees under his belt. Over the course of his runs in Boston and Chicago, he's plucked such stars as Jacoby Ellsbury, Dustin Pedroia, Jonathon Papelbon, Jon Lester, Kevin Youkilis, Kris Bryant, and Kyle Schwarber.

Every professional baseball player has incredible talent. What separates the great ones from the rest, though, is how they handle the mental part of the game.

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"Baseball is a game built on failure," Epstein said. "It's inherent in the game itself. Even the best players get out seven of 10 times ... Everyone gets humbled in baseball. As soon as you think you have it figured out, it will knock you to your knees ... Rely on a solid foundation that you've built up through your life, and then make adjustments."

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