Try non-glare uv glass with your jersey. The difference is truly amazing.
If you have a valuable signed jersey that you want to keep for a lifetime, you should definitely use uv glass as well as archival mats. We also pin in the jersey, not staple or sew it in. No big holes so that you can remove it from the frame and wear it or sell it in ten years. Come in and see what we can do for you.