Authentic Jason Day signed sports memorabilia collectors will love this Jason Day Autographed The Players Flag JSA Authentic from Sports Collectibles. This Jason Day signature comes with a Certificate of Authenticity from JSA. Sports Collectibles is the online leader in 100% authentic Jason Day and autographed collectibles. This particular autograph is in pristine condition and would make for a perfect start to a memorabilia collection. Autographed Jason Day collectibles are hard to find, you are only a few quick clicks away from an authentic Jason Day sports gift.