Peter Crombie, one of the greatest masters champions in history, has retired at age 74. This is the end of a sprinter era. Peter has been a frequent guest entrant at USATF nationals and is a buddy to many Yanks. When I heard from a friend about Peter’s pullout, I was skeptical. Peter is still in his prime! How could this be? So I wrote him. Here’s what I learned: MASTERSTRACK.BLOG: Can you share your status, and reasons for retiring? PETER CROMBIE: Injuries have plagued my athletics career for some 20 years now with knees being the main issue with…