Among the notable NFL rule change proposals was Baltimore's submission regarding the identification of eligible receivers who normally wear ineligible jersey numbers.
The crux of their proposal: A player wearing what is normally an ineligible number (50-79 and 90-99) would put on a "jersey vest" matching the team uniform with an appropriate number for his eligible status.
The Ravens were burned a year ago when offensive lineman John Urschel appeared to declare as eligible against the Cardinals, only to have his first-down catch called back because the officials did not recognize that Urschel had reported as eligible.