Baseball Players Who Took Their Chances and Went Cupless: A History. By Joe DeLessio ... Wrote Jones, about how the two continued to play catch during the off-season: “Arencibia never did wear his cup; fortunately, he never needed it.” 2010 ... I do too many moves to wear a cup. read more
Other players, usually middle infielders, may choose to wear one, but cups are uncomfortable and many won’t wear one for that reason. Some who have been hit by balls between the legs and had a bad experience may wear one. read more
This 2009 article found that the consensus was that catchers wear cups, most outfielders don’t, and it quotes one trainer who estimated that about 25 percent of infielders don’t wear them, either. read more