Here is a situation that occurs in many languages. Let's have a document with many images. Each image has a caption, say, "Illustration 1 - bla bla bla", "Illustration 2 - another bla bla bla". Within the text we reference "Illustration 1 - ..." this way: "According to Illustration 1, the moon is a chunk of cheese" The issue is: "Illustration" in the text has a capital I. Linguistics of many languages tells us to put a lower i when not in the begining of a paragraph. The correct way is "According to illustration 1, the moon is a chunk of cheese" There is no way to have a lower i unless the author drop the field category and stay only with the field number.
Select the reference and right click -> Character -> Font Effects tab, and select Lower-case from Effects. Or you can create a character style with lower case and apply it to the reference. Set to RESOLVED WORKSFORME.