
1966 press conference announcing retirement, as quoted by UPI, in "Sandy Koufax Announces Retirement from Baseball at News Meeting" https://newspaperarchive.com/pittsfield-berkshire-eagle-nov-19-1966-p-30/ by Alex Kahn (UPI), in The Pittsfield Berkshire Eagle (November 19, 1966)
Context: I don't regret one minute of the twelve years I've spent in baseball, but I could regret one season too many. [... ] I've got a lot of years to live after baseball and I would like to live them with complete use of my body.