Supernaw was previously with the Houston Texans after going undrafted out of Ouachita Baptist University in Arkansas, where he was a four-year starter.
At Ouachita Baptist, Supernaw caught 64 passes for 710 yards and 10 touchdowns as a sophomore and was named first-team All-Gulf South Conference. He was later a two-time all-conference second-team selection.
The Texans released Supernaw in May, and he signed with the Ravens that month. He was cut by the Ravens during their final major roster cutdown before the season and joined their practice squad for the first time.
Williams was cut by the Ravens before the start of the regular season.
Williams originally signed with the Ravens as an undrafted free agent in 2011. He spent two seasons with Baltimore, contributing primarily on special teams before being cut twice in the past year.
Last season, Williams signed with the New England Patriots before being cut in November without ever playing in a game for the Patriots.