Dustin Pedroia retired Monday at the age of 37, perfectly middle aged in human terms. In baseball terms, he was finally old, but in real terms he was old the first time he set foot in Fenway Park. That man was spiritually aged 37 for the entirety of his career.
His body has finally, fully caught up. He can no longer really run, which means he really can’t play, not like before, when he merely kinda couldn’t run, and played, and the time before that, which was the same, and the one before that, and that. A lesser player—certainly a lesser defensive player— probably would have officially hung it up earlier.