Since 1977, the NFL has also held a Supplemental Draft to accommodate
players who did not enter the regular draft. Players generally enter the
Supplementary Draft because they missed the filing deadline for the NFL
Draft or because issues developed which affected their eligibility
(such as athletic or disciplinary matters). The draft is scheduled to
occur at some point after the regular draft and before the start of the
next season. In 2009, the Supplemental Draft occurred on July 16 - wiki