What position did Edgar Martínez mostly play, becoming the award's namesake?

What position did Johnny Bench play? What position did Mike Schmidt play? What position did Ken Griffey Jr. mainly play? What position did Mariano Rivera play? MLB's award for the best designated hitter is named after which player? MLB's award for the best reliever in the American League is named after which pitcher? MLB's award for the best reliever in the National League is named after which pitcher? MLB's award for the best hitter in each league is named after which player?