For fans, Opening Day is a celebration of American's pastime.
For general managers, it's the first of many days that will determine their futures. The entire offseason leads up to this day, where win-loss records are supreme and determine which general managers get another year and which get the ax.
Some GMs will lose their jobs because their teams fail to live up to high expectations set by a high payroll. Others will lose because long rebuilding processes have not worked fast enough.
Here are five general managers who could be on the chopping block if their teams don't live up to expectations this year.