The team also placed rookie linebacker Buddy Johnson on the Reserve/Injured List. Johnson has been dealing with a foot injury that has forced him to miss time and had already been ruled out for Sunday before being placed on the list.
Gilliam, who played college ball at Wake Forest, was signed by the Los Angeles Chargers as an undrafted rookie free agent following the 2020 NFL Draft and spent his rookie season on their practice squad.
In other practice squad moves, the team released receivers Rico Bussey and Damion Willis from the practice squad.
Johnson is the Steelers leading receiver with 100 receptions for 1,110 yards, his first 100 reception season and his first 1,000-yard receiving season of his career. Johnson, who has played in 15 games with 14 starts, also has a career-high eight touchdowns.
In addition, the team signed guard Nate Gilliam to the practice squad. Gilliam spent a short stint on the team’s practice squad, signed originally on Dec. 21, but released on Dec. 29.