6. Mariano Rivera

A slender right-handed pitcher with a smooth delivery that concealed the explosive velocity of his fastball. 

That was Mariano Rivera.

While he struggled as a starter, a move to the bullpen in 1996 fundamentally changed the franchise's trajectory. Across 19 seasons in pinstripes, he operated as the most efficient high-leverage weapon in the history of the sport, relying almost exclusively on a signature cut-fastball that shattered bats and shattered the hopes of opposing lineups.

In his first season in the bullpen (’96), Rivera delivered one of the most exceptional relief seasons in baseball history, pitching 107.2 innings with a 2.09 ERA and 130 strikeouts, and finishing third in the Cy Young Award voting. He acted as the key bridge to closer John Wetteland, offering the strategic prowess that helped the Yankees win their first World Series in 18 years. By 1997, he had become the team's primary closer, earning 43 saves and introducing the "born-again" cutter, a pitch that would define his career for the next twenty years.

Between 1998 and 2000, he was the decisive figure in the Yankees' "three-peat" of World Series titles, earning World Series Most Valuable Player honors in 1999 after pitching 4.2 scoreless innings against Atlanta. He demonstrated total mastery of the October stage, ultimately concluding his career with an extraordinary 0.70 ERA and 42 saves across 96 postseason games. Whether he was pitching three shutout innings to secure the 2003 American League Championship Series Most Valuable Player award or recording the final out in five different World Series, he proved to be a formidable figure who grew even larger as the pressure intensified.

His career milestone was achieved on September 19, 2011, at Yankee Stadium, when he recorded his 602nd save, overtaking Trevor Hoffman as the all-time leader. Despite a severe knee injury in 2012 that almost ended his career, he made a remarkable comeback for a spectacular final season in 2013, adding 44 saves at age 43. He retired as the all-time leader with 652 saves and the most games finished, holding a career WHIP of 1.000 and an ERA+ of 205. His legacy was sealed in 2019 when he became the first player ever to be unanimously elected to the National Baseball Hall of Fame, shortly after Yankees retired his No. 42.

There will never be another Mariano Rivera.