On April 15, 1997, then-MLB commissioner Bud Selig announced that the No. 42 of the luminous and pioneering Jackie Robinson would be retired throughout Major League Baseball in perpetuity. It was a fitting honor for the most important figure in modern baseball history. 

As part of the tribute, MLB allowed those active players already wearing No. 42 to continue doing so for the remainder of their careers. One of those was 27-year-old Yankees reliever Mariano Rivera, a washed-out starter who was coming off one of the great relief seasons of his era as John Wetteland's heavily used setup man. Rivera went to pitch for another 17 seasons, which made him the last to wear Robinson's No. 42. 

On Tuesday, Rivera became the first unanimous Hall of Famer in MLB history and, in what likely meant more to Rivera than being named on every BBWAA ballot, the last Hall of Famer to wear Jackie Robinson's number. Said Rivera: 

"It was a beautiful, long career with the best organization there is in baseball, the New York Yankees. And to end up with this [ballot result] like that, it's amazing. One thing I will always remember is wearing No. 42 and representing Mr. Jackie Robinson. He, I assume, was the first No. 42 elected, and me being the last player to wear No. 42 and being elected to the Hall of Fame unanimously is amazing. "

In addition to Robinson and Rivera, Bruce Sutter is the other Hall of Famer to wear No. 42 for at least the majority of his career. Alan Trammell and Bob Lemon wore it for one season, and, coincidentally, another former Yankee who earned election on Tuesday, Mike Mussina, wore No. 42 during his rookie year of 1991 before switching to his familiar No. 35. 

Rivera, though, will be just behind Robinson when it comes to those most associated with this canonized uniform number. Given Rivera's generous spirit and his sterling reputation on and off the field, he again makes a fitting capstone for the proud history of No. 42.