He's Atiyyah Ellison, a 315-pound defensive lineman. Ellison is the personification of a journeyman, having played for Carolina, Baltimore, San Francisco and Jacksonville since the Panthers drafted him out of Missouri in the third round in 2005.
If Ellison is active for Sunday's game against Jacksonville at Arrowhead Stadium, his first contest with Kansas City will come against his most recent team. He started six games for the Jaguars last season.
Ellison takes the roster spot of Alex Magee, who was traded Tuesday to Tampa Bay.