Closer

A closer is the relief pitcher a team trusts to get the final three outs of a game it's winning, and the role exists almost entirely because of one statistic: the save. MLB made saves official in 1969, and once the number became something pitchers and agents could point to in contract talks, teams reorganized entire bullpens around it, holding a team's best reliever for a clean ninth inning instead of using him whenever the game was actually on the line. That's the modern criticism of the role: the highest-leverage moment in a game is sometimes the seventh inning with the bases loaded, not a clean ninth with a three-run lead, but the save rule rewards the latter far more visibly than the former. Analytics-driven front offices increasingly push back against rigid closer usage, though the role, and the save chase, has proven remarkably durable anyway. More on how the role evolved at Bleacher Report.