Closing

Goose Gossage
Wikipedia - "In baseball, a closing pitcher, more frequently referred to as a closer (abbreviated CL), is a relief pitcher who specializes in getting the final outs in a close game when their team is leading. The role is often assigned to a team's best reliever. Before the 1990s, pitchers in similar roles were referred to as a fireman, short reliever, and stopper. A small number of closers have won the Cy Young Award. Dennis Eckersley, Rollie Fingers, Goose Gossage, Bruce Sutter and Hoyt Wilhelm are closers who have been elected to the Baseball Hall of Fame."
Wikipedia
Top 10 Relief Pitchers In Baseball History
NYT: How Mariano Rivera Compares to Baseball’s Best Closers
Britannica: closer
SI: With more closers breaking down, it's time to rethink modern bullpen
amazon: Fireman: The Evolution of the Closer in Baseball