The “best” is subjective.
Several terrific vids in this thread can illustrate what an amazing arm can do.
But Bo certainly had the strongest arm. He overthrew the cutoff man a lot trying to be the “hero”. When he got it right, it was magic. But he was absolutely a work in progress as a baseball player. The coaching kinda finally started clicking in1989.
But if we’re talking “best” arm, that’s gotta be Clemente. Strong, reserved and accurate to where the throw needed to be.
[Reply]