Ness, 27, signed with the Cleveland Browns as an undrafted free agent out of Arizona back in 2009. He has since played for a number of teams including: the Jets, Seahawks, Dolphins, Redskins and Rams.
Ness last appeared in an NFL during the 2011 season.
Greenwood, 29, signed a four-year contract worth $2.75 million with Detroit back in 2012. He still had two years remaining on his current deal with base salaries of $730,000 and $745,000 coming his way during this time.
Greenwood hasn’t appeared in an NFL game since 2012.