I don’t think we are going to have one person dispute us when we are saying that Mariano Rivera is the greatest Relief Pitcher of all time.
The all-time leader in Saves realistically had one pitch; and that fastball was all he needed. Elite firemen shorten a game, but nobody did it longer and better than Rivera did. Nobody actually came close.
What Rivera did was incredible. Not only is he the all-time Saves Leader, he also holds the all-time record for ERA+ and has a career WHIP of 1.000, and four times he had a WHIP under 0.9! Perhaps the most incredible thing about Rivera is how his numbers increased in the post-season as over 96 Games he posted an 8-1 record with a 0.70 ERA, a WHIP of 0.759 with 42 Saves.
This is a legend
Rivera made Baseball Hall of Fame history when in 2019 he was selected by all voters, a Cooperstown first. The Yankees had already retired his number 42 after he retired.