John Mackey Autographed Baltimore Colts Goal Line Art Card Blue HOF 22848 This is a limited edition of 5000, Goal Line Art card which has been personally autographed by John Mackey with HOF inscription in blue sharpie. From the original done by Gary Thomas, card measures 4x 6 and is mint condition. This was signed at the Collectors Showcase of America card show on July 12, 2009 and includes a certificate of authenticity from Denver Autographs.