“Just the nature of working here, day after day, it’s a huge grind,” Newman added. “There are tremendous stresses to deal with, and it can wear you out. Everybody needs to take a deep breath once in a while, take a step back and make sure they’re not going to burn out. But he knows the situation.”

Cashman started as an intern in the minor league and scouting department at 19, and he was 30 when he became the general manager. Only three other general managers who were on the job then are still in the same job now.
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Pat Gillick, the Philadelphia Phillies’ general manager, once resigned as the Baltimore Orioles’ G.M. because of differences with the owner, Peter Angelos. Speaking generally, Gillick said, an owner who interferes with baseball decisions risks losing his best people.

“What it does is erode some of the confidence of the people working for you,” Gillick said. “There’s a chain of command and a code of conduct that has to be followed by every member of an organization. When that’s broken, it’s not good.”

Gillick said Cashman and Epstein probably had the most difficult job of any general manager, because their resources were so deep that they had more decisions to make. No situation can be immediately dismissed for financial reasons, so every available player must be evaluated.