This Autographed Blue Rookie Of The Year All Decade 2011-2020 Nike Select Jersey has been Personally Signed by Luka Doncic of the Dallas Mavericks. This item is 100% Authentic to include a Certificate of Authenticity (COA) / hologram by Beckett Authentication Services. The authenticity can be verified on Beckett Authentication Services website. This is a XX-Large sized Jersey.