Ham as Nickname

[Gina]

Hello,

May you know the origin of Ham as Nickname in Baseball, like Ham Hyatt?

http://www.fangraphs.com/not/index.php/seven-players-named-ham/

Some says it from Ham-handed others from Ham-fatter.

[westsidegrounds]

In Hyatt's case it's simply a short version of his name - Robert Hamilton Hyatt.

Same for Hamilton "Ham" Patterson and Thomas "Ham" Hamilton.

None of them seem to qualify as "19th Century" players, by the way.