Mariano Rivera is a Panamanian right-handed baseball pitcher who has spent his entire Major League Baseball (MLB) career with the New York Yankees. Nicknamed "Mo", Rivera has served as a relief pitcher for most of his career, and since 1997, he has been the Yankees' closer. An 11-time All-Star and five-time World Series champion, Rivera has accumulated 559 saves, the second-most in MLB history. He holds Major League postseason records for saves and earned run average (ERA), among other records. Rivera is regarded as one of the greatest closers in baseball history.