Simpkins, a 6-foot, 236-pound first-year player out of Coastal Carolina, has been on Green Bay’s practice squad for the first four games. Signed by the Packers as a free agent in August, Simpkins played for the Green Bay Blizzard of the Indoor Football League in 2010. He will wear No. 53.
Williams, a 6-foot-2, 244-pound first-year player out of the University of Kentucky, entered the NFL as a non-drafted free agent with Jacksonville in May 2009. He spent time on Pittsburgh’s practice squad late in the 2009 season and was with Denver during the preseason this year. Williams will wear No. 48.
Burnett sustained a knee injury in last Sunday’s game vs. Detroit.