The Belt changes hands shortly after season’s end, in a crowded conference room at a luxury resort, where delegates from every MLB team have been summoned for a symposium on arbitration. For three hours, they will work together at the direction of the league to set recommendations, which teams will use in negotiations with their players. It’s a thankless job. So before the meeting adjourns, they’ll celebrate an unsung hero in this battle over dollars. The ceremony ends with the presentation of a replica championship belt, awarded by the league to the team that did most to “achieve the goals set by the industry.” In other words: The team that did the most to keep salaries down in arbitration.



For the last few years, The Belt has been an urban legend of sorts, known mostly by player agents and the small circle of mid-level team officials tasked with the tedious process of arbitration. But its existence, confirmed to The Athletic by multiple sources,...