Originally drafted out of Montana in the seventh round of the 2010 NFL Draft by Tennessee, the 29-year-old Mariani spent four seasons in Nashville but lost both the 2012 and 2013 campaigns to injury.
He was released by the team in August 2014.
“I was here with Marc (Mariani) in 2014,” coach Mike Mularkey told the media after Monday’s practice. “I know what he’s done in the past. Really his return ability is what we were looking at. Really it gives us somebody in both areas that we can use as a returner that has been to the Pro Bowl because of it. He’s had a lot of success. It was good for this team. This team is excited to have him back. I think the fans will be, as well. He’s one of these guys we’ve been talking about—tough, dependable and team-first. He fits right in with us right away.”
WR/KR Marc Mariani will wear No. 87, CB Cody Riggs switches to 24, per #Titans.
— Jason Wolf (@JasonWolf) September 5, 2016
As a corresponding roster move, the Titans released receiver Tre McBride.
Mariani has three returns for touchdowns in his career, averaging 26.1 yards on kickoff returns and 6.6 yards-per-return on punts last season. He returned kicks only 16 times in 2015 for the Bears. As a receiver for Chicago, Mariani recorded 22 catches for 300 yards.
Information from ESPN.com, The Tennessean and TitansOnline.com contributed to this report.