J.J. Cooper of Baseball America first repored it, covered by MLBTR:
Mike Hessman has announced his retirement, J.J. Cooper of Baseball America notes. Hessman initially tweeted that he was retiring to become a coach, although that tweet has since been deleted.
Hessman’s retirement is a move that is minor by definition but more noteworthy than that term suggests — among fans of minor league baseball, Hessman’s career will be remembered as legendary. No minor league slugger, in fact, has been more prolific — this season, the 37-year-old Hessman topped Buzz Arlett’s all-time record with his 433rd career minor league homer.
The Braves selected Hessman in the 15th round all the way back in 1996 — a draft in which they also took Jason Marquis, Mark DeRosa and Marcus Giles, which gives a sense of just how long Hessman was in the minors. He reached Triple-A six years later and made his big-league debut in 2003.
Hessman ultimately played parts of five big-league seasons with the Braves, Tigers and Mets, although he never collected even 100 plate appearances in a single year. Instead, he bounced from one organization to the next, hitting one home run after another for various Triple-A teams and playing in over 2,000 minor league games. The team with which he’ll be most strongly connected is the Toledo Mud Hens, for whom he played from 2005-2009 and 2014-2015. Hessman hit 23 or more homers in his first six seasons in Toledo before finishing with 16 last season. Overall, he hit 20 or more minor-league homers 13 times in his career. He also helped the US baseball team to a bronze medal in the 2008 Summer Olympics in Beijing, and in 2009 he attracted attention by playing all nine positions in a single game for the Mud Hens.