After clearing waivers, second-year safety Mike Hamlin has joined the Jacksonville Jaguars practice squad, reports Tania Ganguli of the Florida Times-Union reports.

Quarterback Keith Null has been released.

A fifth-round pick (166th overall) out of Clemson in 2009, Hamlin appeared in 8 games for the Cowboys over the last two seasons, totaling one special teams tackle. During his 48-game college career, Hamlin (6-2, 218) registered 326 tackles and picked off 14 passes.