[Dilbert San Diego]

I heard somebody say he became a relief pitcher because he couldn’t make it as a starter, early in his career. And as fate would have it, being a relief pitcher was the role he then excelled at.

Is that true?

Whatever the case, he became one of the greatest relief pitchers of all time. When his manager gave him the ball, he got the job done.

He helped redefine the 9th inning reliever or “closer” role, from what I hear.

[C19fan]

There was already the 9th inning relief specialist when Rivera entered the league. It was Tony LaRusa using Dennis Eckersley who established that role.

[FreeReign]

I heard somebody say he became a relief pitcher because he couldn’t make it as a starter, early in his career. And as fate would have it, being a relief pitcher was the role he then excelled at. Is that true? Whatever the case, he became one of the greatest relief pitchers of all time. When his manager gave him the ball, he got the job done.

He was okay as a starter. But you need multiple good pitches to really succeed as a starter. Mo had one great pitch, possibly the most deceptive pitch of all time.

Some rate Mo's cutter as the best pitch of all time.

10 OF THE BEST PITCHES IN BASEBALL HISTORY

So he became a Hall of Fame RP.

[Rummyfan]

I heard somebody say he became a relief pitcher because he couldn’t make it as a starter, early in his career.

You could say that about just about every reliever. There's a reason they're not starters: their not good enough!