Mulligan signed with the Cardinals on Tuesday, Aaron Wilson of the Baltimore Sun reports. Mulligan will provide the Cardinals with tight end depth after the team lost rookie Troy Niklas to a season-ending ankle injury. The team already has John Carlson, Rob Housler and Darren Fells ahead of Mulligan on the depth chart, so it's unlikely he'll be featured heavily in the offensive game plan this season. It took him over two months since being released by the Bears to sign on elsewhere, as the 29-year-old hasn't recorded a reception in the league since his time with the Patriots in 2013.